Remove mempools and buf freelists

They have been off-by-default since 0.2.5 and nobody has complained. :)

Also remove the buf_shrink() function, which hasn't done anything
since we first stopped using contiguous memory to store buffers.

Closes ticket 14848.

11 files changed, 9 insertions, 1080 deletions

diff --git a/changes/remove_mempools b/changes/remove_mempools
new file mode 100644
index 0000000000..8acaf29cfa
--- /dev/null
+++ b/changes/remove_mempools
@@ -0,0 +1,5 @@
+  o Removed features:
+    - The --enable-mempool and --enable-buf-freelists options, which
+      were originally created to work around bad malloc implementations,
+      no longer exist.  They were off-by-default in 0.2.5.  Closes
+      ticket 14848.
diff --git a/configure.ac b/configure.ac
index 8daddf03c6..46af18f6fa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -25,10 +25,6 @@ fi
 CPPFLAGS="$CPPFLAGS -I\${top_srcdir}/src/common"
 
 #XXXX020 We should make these enabled or not, before 0.2.0.x-final
-AC_ARG_ENABLE(buf-freelists,
-   AS_HELP_STRING(--enable-buf-freelists, enable freelists for buffer RAM))
-AC_ARG_ENABLE(mempools,
-   AS_HELP_STRING(--enable-mempools, enable mempools for relay cells))
 AC_ARG_ENABLE(openbsd-malloc,
    AS_HELP_STRING(--enable-openbsd-malloc, Use malloc code from openbsd.  Linux only))
 AC_ARG_ENABLE(instrument-downloads,
diff --git a/src/common/include.am b/src/common/include.am
index 14838ab555..5b63392541 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -24,14 +24,6 @@ else
 libor_extra_source=
 endif
 
-if USE_MEMPOOLS
-libor_mempool_source=src/common/mempool.c
-libor_mempool_header=src/common/mempool.h
-else
-libor_mempool_source=
-libor_mempool_header=
-endif
-
 src_common_libcurve25519_donna_a_CFLAGS=
 
 if BUILD_CURVE25519_DONNA
@@ -78,7 +70,6 @@ LIBOR_A_SOURCES = \
   src/ext/csiphash.c					\
   src/ext/trunnel/trunnel.c				\
   $(libor_extra_source)					\
-  $(libor_mempool_source)				\
   $(threads_impl_source)
 
 LIBOR_CRYPTO_A_SOURCES = \
@@ -138,8 +129,7 @@ COMMONHEADERS = \
   src/common/tortls.h				\
   src/common/util.h				\
   src/common/util_process.h			\
-  src/common/workqueue.h			\
-  $(libor_mempool_header)
+  src/common/workqueue.h
 
 noinst_HEADERS+= $(COMMONHEADERS)
 
diff --git a/src/common/mempool.c b/src/common/mempool.c
deleted file mode 100644
index 55a34070d7..0000000000
--- a/src/common/mempool.c
+++ /dev/null
@@ -1,628 +0,0 @@
-/* Copyright (c) 2007-2015, The Tor Project, Inc. */
-/* See LICENSE for licensing information */
-#if 1
-/* Tor dependencies */
-#include "orconfig.h"
-#endif
-
-#include <stdlib.h>
-#include <string.h>
-#include "torint.h"
-#include "crypto.h"
-#define MEMPOOL_PRIVATE
-#include "mempool.h"
-
-/* OVERVIEW:
- *
- *     This is an implementation of memory pools for Tor cells.  It may be
- *     useful for you too.
- *
- *     Generally, a memory pool is an allocation strategy optimized for large
- *     numbers of identically-sized objects.  Rather than the elaborate arena
- *     and coalescing strategies you need to get good performance for a
- *     general-purpose malloc(), pools use a series of large memory "chunks",
- *     each of which is carved into a bunch of smaller "items" or
- *     "allocations".
- *
- *     To get decent performance, you need to:
- *        - Minimize the number of times you hit the underlying allocator.
- *        - Try to keep accesses as local in memory as possible.
- *        - Try to keep the common case fast.
- *
- *     Our implementation uses three lists of chunks per pool.  Each chunk can
- *     be either "full" (no more room for items); "empty" (no items); or
- *     "used" (not full, not empty).  There are independent doubly-linked
- *     lists for each state.
- *
- * CREDIT:
- *
- *     I wrote this after looking at 3 or 4 other pooling allocators, but
- *     without copying.  The strategy this most resembles (which is funny,
- *     since that's the one I looked at longest ago) is the pool allocator
- *     underlying Python's obmalloc code.  Major differences from obmalloc's
- *     pools are:
- *       - We don't even try to be threadsafe.
- *       - We only handle objects of one size.
- *       - Our list of empty chunks is doubly-linked, not singly-linked.
- *         (This could change pretty easily; it's only doubly-linked for
- *         consistency.)
- *       - We keep a list of full chunks (so we can have a "nuke everything"
- *         function).  Obmalloc's pools leave full chunks to float unanchored.
- *
- * LIMITATIONS:
- *   - Not even slightly threadsafe.
- *   - Likes to have lots of items per chunks.
- *   - One pointer overhead per allocated thing.  (The alternative is
- *     something like glib's use of an RB-tree to keep track of what
- *     chunk any given piece of memory is in.)
- *   - Only aligns allocated things to void* level: redefine ALIGNMENT_TYPE
- *     if you need doubles.
- *   - Could probably be optimized a bit; the representation contains
- *     a bit more info than it really needs to have.
- */
-
-#if 1
-/* Tor dependencies */
-#include "util.h"
-#include "compat.h"
-#include "torlog.h"
-#define ALLOC(x) tor_malloc(x)
-#define FREE(x) tor_free(x)
-#define ASSERT(x) tor_assert(x)
-#undef ALLOC_CAN_RETURN_NULL
-#define TOR
-/* End Tor dependencies */
-#else
-/* If you're not building this as part of Tor, you'll want to define the
- * following macros.  For now, these should do as defaults.
- */
-#include <assert.h>
-#define PREDICT_UNLIKELY(x) (x)
-#define PREDICT_LIKELY(x) (x)
-#define ALLOC(x) malloc(x)
-#define FREE(x) free(x)
-#define STRUCT_OFFSET(tp, member)                       \
-  ((off_t) (((char*)&((tp*)0)->member)-(char*)0))
-#define ASSERT(x) assert(x)
-#define ALLOC_CAN_RETURN_NULL
-#endif
-
-/* Tuning parameters */
-/** Largest type that we need to ensure returned memory items are aligned to.
- * Change this to "double" if we need to be safe for structs with doubles. */
-#define ALIGNMENT_TYPE void *
-/** Increment that we need to align allocated. */
-#define ALIGNMENT sizeof(ALIGNMENT_TYPE)
-/** Largest memory chunk that we should allocate. */
-#define MAX_CHUNK (8*(1L<<20))
-/** Smallest memory chunk size that we should allocate. */
-#define MIN_CHUNK 4096
-
-typedef struct mp_allocated_t mp_allocated_t;
-typedef struct mp_chunk_t mp_chunk_t;
-
-/** Holds a single allocated item, allocated as part of a chunk. */
-struct mp_allocated_t {
-  /** The chunk that this item is allocated in.  This adds overhead to each
-   * allocated item, thus making this implementation inappropriate for
-   * very small items. */
-  mp_chunk_t *in_chunk;
-  union {
-    /** If this item is free, the next item on the free list. */
-    mp_allocated_t *next_free;
-    /** If this item is not free, the actual memory contents of this item.
-     * (Not actual size.) */
-    char mem[1];
-    /** An extra element to the union to insure correct alignment. */
-    ALIGNMENT_TYPE dummy_;
-  } u;
-};
-
-/** 'Magic' value used to detect memory corruption. */
-#define MP_CHUNK_MAGIC 0x09870123
-
-/** A chunk of memory.  Chunks come from malloc; we use them  */
-struct mp_chunk_t {
-  unsigned long magic; /**< Must be MP_CHUNK_MAGIC if this chunk is valid. */
-  mp_chunk_t *next; /**< The next free, used, or full chunk in sequence. */
-  mp_chunk_t *prev; /**< The previous free, used, or full chunk in sequence. */
-  mp_pool_t *pool; /**< The pool that this chunk is part of. */
-  /** First free item in the freelist for this chunk.  Note that this may be
-   * NULL even if this chunk is not at capacity: if so, the free memory at
-   * next_mem has not yet been carved into items.
-   */
-  mp_allocated_t *first_free;
-  int n_allocated; /**< Number of currently allocated items in this chunk. */
-  int capacity; /**< Number of items that can be fit into this chunk. */
-  size_t mem_size; /**< Number of usable bytes in mem. */
-  char *next_mem; /**< Pointer into part of <b>mem</b> not yet carved up. */
-  char mem[FLEXIBLE_ARRAY_MEMBER]; /**< Storage for this chunk. */
-};
-
-/** Number of extra bytes needed beyond mem_size to allocate a chunk. */
-#define CHUNK_OVERHEAD STRUCT_OFFSET(mp_chunk_t, mem[0])
-
-/** Given a pointer to a mp_allocated_t, return a pointer to the memory
- * item it holds. */
-#define A2M(a) (&(a)->u.mem)
-/** Given a pointer to a memory_item_t, return a pointer to its enclosing
- * mp_allocated_t. */
-#define M2A(p) ( ((char*)p) - STRUCT_OFFSET(mp_allocated_t, u.mem) )
-
-#ifdef ALLOC_CAN_RETURN_NULL
-/** If our ALLOC() macro can return NULL, check whether <b>x</b> is NULL,
- * and if so, return NULL. */
-#define CHECK_ALLOC(x)                           \
-  if (PREDICT_UNLIKELY(!x)) { return NULL; }
-#else
-/** If our ALLOC() macro can't return NULL, do nothing. */
-#define CHECK_ALLOC(x)
-#endif
-
-/** Helper: Allocate and return a new memory chunk for <b>pool</b>.  Does not
- * link the chunk into any list. */
-static mp_chunk_t *
-mp_chunk_new(mp_pool_t *pool)
-{
-  size_t sz = pool->new_chunk_capacity * pool->item_alloc_size;
-  mp_chunk_t *chunk = ALLOC(CHUNK_OVERHEAD + sz);
-
-#ifdef MEMPOOL_STATS
-  ++pool->total_chunks_allocated;
-#endif
-  CHECK_ALLOC(chunk);
-  memset(chunk, 0, sizeof(mp_chunk_t)); /* Doesn't clear the whole thing. */
-  chunk->magic = MP_CHUNK_MAGIC;
-  chunk->capacity = pool->new_chunk_capacity;
-  chunk->mem_size = sz;
-  chunk->next_mem = chunk->mem;
-  chunk->pool = pool;
-  return chunk;
-}
-
-/** Take a <b>chunk</b> that has just been allocated or removed from
- * <b>pool</b>'s empty chunk list, and add it to the head of the used chunk
- * list. */
-static INLINE void
-add_newly_used_chunk_to_used_list(mp_pool_t *pool, mp_chunk_t *chunk)
-{
-  chunk->next = pool->used_chunks;
-  if (chunk->next)
-    chunk->next->prev = chunk;
-  pool->used_chunks = chunk;
-  ASSERT(!chunk->prev);
-}
-
-/** Return a newly allocated item from <b>pool</b>. */
-void *
-mp_pool_get(mp_pool_t *pool)
-{
-  mp_chunk_t *chunk;
-  mp_allocated_t *allocated;
-
-  if (PREDICT_LIKELY(pool->used_chunks != NULL)) {
-    /* Common case: there is some chunk that is neither full nor empty.  Use
-     * that one. (We can't use the full ones, obviously, and we should fill
-     * up the used ones before we start on any empty ones. */
-    chunk = pool->used_chunks;
-
-  } else if (pool->empty_chunks) {
-    /* We have no used chunks, but we have an empty chunk that we haven't
-     * freed yet: use that.  (We pull from the front of the list, which should
-     * get us the most recently emptied chunk.) */
-    chunk = pool->empty_chunks;
-
-    /* Remove the chunk from the empty list. */
-    pool->empty_chunks = chunk->next;
-    if (chunk->next)
-      chunk->next->prev = NULL;
-
-    /* Put the chunk on the 'used' list*/
-    add_newly_used_chunk_to_used_list(pool, chunk);
-
-    ASSERT(!chunk->prev);
-    --pool->n_empty_chunks;
-    if (pool->n_empty_chunks < pool->min_empty_chunks)
-      pool->min_empty_chunks = pool->n_empty_chunks;
-  } else {
-    /* We have no used or empty chunks: allocate a new chunk. */
-    chunk = mp_chunk_new(pool);
-    CHECK_ALLOC(chunk);
-
-    /* Add the new chunk to the used list. */
-    add_newly_used_chunk_to_used_list(pool, chunk);
-  }
-
-  ASSERT(chunk->n_allocated < chunk->capacity);
-
-  if (chunk->first_free) {
-    /* If there's anything on the chunk's freelist, unlink it and use it. */
-    allocated = chunk->first_free;
-    chunk->first_free = allocated->u.next_free;
-    allocated->u.next_free = NULL; /* For debugging; not really needed. */
-    ASSERT(allocated->in_chunk == chunk);
-  } else {
-    /* Otherwise, the chunk had better have some free space left on it. */
-    ASSERT(chunk->next_mem + pool->item_alloc_size <=
-           chunk->mem + chunk->mem_size);
-
-    /* Good, it did.  Let's carve off a bit of that free space, and use
-     * that. */
-    allocated = (void*)chunk->next_mem;
-    chunk->next_mem += pool->item_alloc_size;
-    allocated->in_chunk = chunk;
-    allocated->u.next_free = NULL; /* For debugging; not really needed. */
-  }
-
-  ++chunk->n_allocated;
-#ifdef MEMPOOL_STATS
-  ++pool->total_items_allocated;
-#endif
-
-  if (PREDICT_UNLIKELY(chunk->n_allocated == chunk->capacity)) {
-    /* This chunk just became full. */
-    ASSERT(chunk == pool->used_chunks);
-    ASSERT(chunk->prev == NULL);
-
-    /* Take it off the used list. */
-    pool->used_chunks = chunk->next;
-    if (chunk->next)
-      chunk->next->prev = NULL;
-
-    /* Put it on the full list. */
-    chunk->next = pool->full_chunks;
-    if (chunk->next)
-      chunk->next->prev = chunk;
-    pool->full_chunks = chunk;
-  }
-  /* And return the memory portion of the mp_allocated_t. */
-  return A2M(allocated);
-}
-
-/** Return an allocated memory item to its memory pool. */
-void
-mp_pool_release(void *item)
-{
-  mp_allocated_t *allocated = (void*) M2A(item);
-  mp_chunk_t *chunk = allocated->in_chunk;
-
-  ASSERT(chunk);
-  ASSERT(chunk->magic == MP_CHUNK_MAGIC);
-  ASSERT(chunk->n_allocated > 0);
-
-  allocated->u.next_free = chunk->first_free;
-  chunk->first_free = allocated;
-
-  if (PREDICT_UNLIKELY(chunk->n_allocated == chunk->capacity)) {
-    /* This chunk was full and is about to be used. */
-    mp_pool_t *pool = chunk->pool;
-    /* unlink from the full list  */
-    if (chunk->prev)
-      chunk->prev->next = chunk->next;
-    if (chunk->next)
-      chunk->next->prev = chunk->prev;
-    if (chunk == pool->full_chunks)
-      pool->full_chunks = chunk->next;
-
-    /* link to the used list. */
-    chunk->next = pool->used_chunks;
-    chunk->prev = NULL;
-    if (chunk->next)
-      chunk->next->prev = chunk;
-    pool->used_chunks = chunk;
-  } else if (PREDICT_UNLIKELY(chunk->n_allocated == 1)) {
-    /* This was used and is about to be empty. */
-    mp_pool_t *pool = chunk->pool;
-
-    /* Unlink from the used list */
-    if (chunk->prev)
-      chunk->prev->next = chunk->next;
-    if (chunk->next)
-      chunk->next->prev = chunk->prev;
-    if (chunk == pool->used_chunks)
-      pool->used_chunks = chunk->next;
-
-    /* Link to the empty list */
-    chunk->next = pool->empty_chunks;
-    chunk->prev = NULL;
-    if (chunk->next)
-      chunk->next->prev = chunk;
-    pool->empty_chunks = chunk;
-
-    /* Reset the guts of this chunk to defragment it, in case it gets
-     * used again. */
-    chunk->first_free = NULL;
-    chunk->next_mem = chunk->mem;
-
-    ++pool->n_empty_chunks;
-  }
-  --chunk->n_allocated;
-}
-
-/** Allocate a new memory pool to hold items of size <b>item_size</b>. We'll
- * try to fit about <b>chunk_capacity</b> bytes in each chunk. */
-mp_pool_t *
-mp_pool_new(size_t item_size, size_t chunk_capacity)
-{
-  mp_pool_t *pool;
-  size_t alloc_size, new_chunk_cap;
-
-  tor_assert(item_size < SIZE_T_CEILING);
-  tor_assert(chunk_capacity < SIZE_T_CEILING);
-  tor_assert(SIZE_T_CEILING / item_size > chunk_capacity);
-
-  pool = ALLOC(sizeof(mp_pool_t));
-  CHECK_ALLOC(pool);
-  memset(pool, 0, sizeof(mp_pool_t));
-
-  /* First, we figure out how much space to allow per item.  We'll want to
-   * use make sure we have enough for the overhead plus the item size. */
-  alloc_size = (size_t)(STRUCT_OFFSET(mp_allocated_t, u.mem) + item_size);
-  /* If the item_size is less than sizeof(next_free), we need to make
-   * the allocation bigger. */
-  if (alloc_size < sizeof(mp_allocated_t))
-    alloc_size = sizeof(mp_allocated_t);
-
-  /* If we're not an even multiple of ALIGNMENT, round up. */
-  if (alloc_size % ALIGNMENT) {
-    alloc_size = alloc_size + ALIGNMENT - (alloc_size % ALIGNMENT);
-  }
-  if (alloc_size < ALIGNMENT)
-    alloc_size = ALIGNMENT;
-  ASSERT((alloc_size % ALIGNMENT) == 0);
-
-  /* Now we figure out how many items fit in each chunk.  We need to fit at
-   * least 2 items per chunk. No chunk can be more than MAX_CHUNK bytes long,
-   * or less than MIN_CHUNK. */
-  if (chunk_capacity > MAX_CHUNK)
-    chunk_capacity = MAX_CHUNK;
-  /* Try to be around a power of 2 in size, since that's what allocators like
-   * handing out. 512K-1 byte is a lot better than 512K+1 byte. */
-  chunk_capacity = (size_t) round_to_power_of_2(chunk_capacity);
-  while (chunk_capacity < alloc_size * 2 + CHUNK_OVERHEAD)
-    chunk_capacity *= 2;
-  if (chunk_capacity < MIN_CHUNK)
-    chunk_capacity = MIN_CHUNK;
-
-  new_chunk_cap = (chunk_capacity-CHUNK_OVERHEAD) / alloc_size;
-  tor_assert(new_chunk_cap < INT_MAX);
-  pool->new_chunk_capacity = (int)new_chunk_cap;
-
-  pool->item_alloc_size = alloc_size;
-
-  log_debug(LD_MM, "Capacity is %lu, item size is %lu, alloc size is %lu",
-            (unsigned long)pool->new_chunk_capacity,
-            (unsigned long)pool->item_alloc_size,
-            (unsigned long)(pool->new_chunk_capacity*pool->item_alloc_size));
-
-  return pool;
-}
-
-/** Helper function for qsort: used to sort pointers to mp_chunk_t into
- * descending order of fullness. */
-static int
-mp_pool_sort_used_chunks_helper(const void *_a, const void *_b)
-{
-  mp_chunk_t *a = *(mp_chunk_t**)_a;
-  mp_chunk_t *b = *(mp_chunk_t**)_b;
-  return b->n_allocated - a->n_allocated;
-}
-
-/** Sort the used chunks in <b>pool</b> into descending order of fullness,
- * so that we preferentially fill up mostly full chunks before we make
- * nearly empty chunks less nearly empty. */
-static void
-mp_pool_sort_used_chunks(mp_pool_t *pool)
-{
-  int i, n=0, inverted=0;
-  mp_chunk_t **chunks, *chunk;
-  for (chunk = pool->used_chunks; chunk; chunk = chunk->next) {
-    ++n;
-    if (chunk->next && chunk->next->n_allocated > chunk->n_allocated)
-      ++inverted;
-  }
-  if (!inverted)
-    return;
-  //printf("Sort %d/%d\n",inverted,n);
-  chunks = ALLOC(sizeof(mp_chunk_t *)*n);
-#ifdef ALLOC_CAN_RETURN_NULL
-  if (PREDICT_UNLIKELY(!chunks)) return;
-#endif
-  for (i=0,chunk = pool->used_chunks; chunk; chunk = chunk->next)
-    chunks[i++] = chunk;
-  qsort(chunks, n, sizeof(mp_chunk_t *), mp_pool_sort_used_chunks_helper);
-  pool->used_chunks = chunks[0];
-  chunks[0]->prev = NULL;
-  for (i=1;i<n;++i) {
-    chunks[i-1]->next = chunks[i];
-    chunks[i]->prev = chunks[i-1];
-  }
-  chunks[n-1]->next = NULL;
-  FREE(chunks);
-  mp_pool_assert_ok(pool);
-}
-
-/** If there are more than <b>n</b> empty chunks in <b>pool</b>, free the
- * excess ones that have been empty for the longest. If
- * <b>keep_recently_used</b> is true, do not free chunks unless they have been
- * empty since the last call to this function.
- **/
-void
-mp_pool_clean(mp_pool_t *pool, int n_to_keep, int keep_recently_used)
-{
-  mp_chunk_t *chunk, **first_to_free;
-
-  mp_pool_sort_used_chunks(pool);
-  ASSERT(n_to_keep >= 0);
-
-  if (keep_recently_used) {
-    int n_recently_used = pool->n_empty_chunks - pool->min_empty_chunks;
-    if (n_to_keep < n_recently_used)
-      n_to_keep = n_recently_used;
-  }
-
-  ASSERT(n_to_keep >= 0);
-
-  first_to_free = &pool->empty_chunks;
-  while (*first_to_free && n_to_keep > 0) {
-    first_to_free = &(*first_to_free)->next;
-    --n_to_keep;
-  }
-  if (!*first_to_free) {
-    pool->min_empty_chunks = pool->n_empty_chunks;
-    return;
-  }
-
-  chunk = *first_to_free;
-  while (chunk) {
-    mp_chunk_t *next = chunk->next;
-    chunk->magic = 0xdeadbeef;
-    FREE(chunk);
-#ifdef MEMPOOL_STATS
-    ++pool->total_chunks_freed;
-#endif
-    --pool->n_empty_chunks;
-    chunk = next;
-  }
-
-  pool->min_empty_chunks = pool->n_empty_chunks;
-  *first_to_free = NULL;
-}
-
-/** Helper: Given a list of chunks, free all the chunks in the list. */
-static void
-destroy_chunks(mp_chunk_t *chunk)
-{
-  mp_chunk_t *next;
-  while (chunk) {
-    chunk->magic = 0xd3adb33f;
-    next = chunk->next;
-    FREE(chunk);
-    chunk = next;
-  }
-}
-
-/** Free all space held in <b>pool</b>  This makes all pointers returned from
- * mp_pool_get(<b>pool</b>) invalid. */
-void
-mp_pool_destroy(mp_pool_t *pool)
-{
-  destroy_chunks(pool->empty_chunks);
-  destroy_chunks(pool->used_chunks);
-  destroy_chunks(pool->full_chunks);
-  memwipe(pool, 0xe0, sizeof(mp_pool_t));
-  FREE(pool);
-}
-
-/** Helper: make sure that a given chunk list is not corrupt. */
-static int
-assert_chunks_ok(mp_pool_t *pool, mp_chunk_t *chunk, int empty, int full)
-{
-  mp_allocated_t *allocated;
-  int n = 0;
-  if (chunk)
-    ASSERT(chunk->prev == NULL);
-
-  while (chunk) {
-    n++;
-    ASSERT(chunk->magic == MP_CHUNK_MAGIC);
-    ASSERT(chunk->pool == pool);
-    for (allocated = chunk->first_free; allocated;
-         allocated = allocated->u.next_free) {
-      ASSERT(allocated->in_chunk == chunk);
-    }
-    if (empty)
-      ASSERT(chunk->n_allocated == 0);
-    else if (full)
-      ASSERT(chunk->n_allocated == chunk->capacity);
-    else
-      ASSERT(chunk->n_allocated > 0 && chunk->n_allocated < chunk->capacity);
-
-    ASSERT(chunk->capacity == pool->new_chunk_capacity);
-
-    ASSERT(chunk->mem_size ==
-           pool->new_chunk_capacity * pool->item_alloc_size);
-
-    ASSERT(chunk->next_mem >= chunk->mem &&
-           chunk->next_mem <= chunk->mem + chunk->mem_size);
-
-    if (chunk->next)
-      ASSERT(chunk->next->prev == chunk);
-
-    chunk = chunk->next;
-  }
-  return n;
-}
-
-/** Fail with an assertion if <b>pool</b> is not internally consistent. */
-void
-mp_pool_assert_ok(mp_pool_t *pool)
-{
-  int n_empty;
-
-  n_empty = assert_chunks_ok(pool, pool->empty_chunks, 1, 0);
-  assert_chunks_ok(pool, pool->full_chunks, 0, 1);
-  assert_chunks_ok(pool, pool->used_chunks, 0, 0);
-
-  ASSERT(pool->n_empty_chunks == n_empty);
-}
-
-#ifdef TOR
-/** Dump information about <b>pool</b>'s memory usage to the Tor log at level
- * <b>severity</b>. */
-/*FFFF uses Tor logging functions. */
-void
-mp_pool_log_status(mp_pool_t *pool, int severity)
-{
-  uint64_t bytes_used = 0;
-  uint64_t bytes_allocated = 0;
-  uint64_t bu = 0, ba = 0;
-  mp_chunk_t *chunk;
-  int n_full = 0, n_used = 0;
-
-  ASSERT(pool);
-
-  for (chunk = pool->empty_chunks; chunk; chunk = chunk->next) {
-    bytes_allocated += chunk->mem_size;
-  }
-  log_fn(severity, LD_MM, U64_FORMAT" bytes in %d empty chunks",
-         U64_PRINTF_ARG(bytes_allocated), pool->n_empty_chunks);
-  for (chunk = pool->used_chunks; chunk; chunk = chunk->next) {
-    ++n_used;
-    bu += chunk->n_allocated * pool->item_alloc_size;
-    ba += chunk->mem_size;
-    log_fn(severity, LD_MM, "   used chunk: %d items allocated",
-           chunk->n_allocated);
-  }
-  log_fn(severity, LD_MM, U64_FORMAT"/"U64_FORMAT
-         " bytes in %d partially full chunks",
-         U64_PRINTF_ARG(bu), U64_PRINTF_ARG(ba), n_used);
-  bytes_used += bu;
-  bytes_allocated += ba;
-  bu = ba = 0;
-  for (chunk = pool->full_chunks; chunk; chunk = chunk->next) {
-    ++n_full;
-    bu += chunk->n_allocated * pool->item_alloc_size;
-    ba += chunk->mem_size;
-  }
-  log_fn(severity, LD_MM, U64_FORMAT"/"U64_FORMAT
-         " bytes in %d full chunks",
-         U64_PRINTF_ARG(bu), U64_PRINTF_ARG(ba), n_full);
-  bytes_used += bu;
-  bytes_allocated += ba;
-
-  log_fn(severity, LD_MM, "Total: "U64_FORMAT"/"U64_FORMAT" bytes allocated "
-         "for cell pools are full.",
-         U64_PRINTF_ARG(bytes_used), U64_PRINTF_ARG(bytes_allocated));
-
-#ifdef MEMPOOL_STATS
-  log_fn(severity, LD_MM, U64_FORMAT" cell allocations ever; "
-         U64_FORMAT" chunk allocations ever; "
-         U64_FORMAT" chunk frees ever.",
-         U64_PRINTF_ARG(pool->total_items_allocated),
-         U64_PRINTF_ARG(pool->total_chunks_allocated),
-         U64_PRINTF_ARG(pool->total_chunks_freed));
-#endif
-}
-#endif
-
diff --git a/src/common/mempool.h b/src/common/mempool.h
deleted file mode 100644
index 5cbeb8f482..0000000000
--- a/src/common/mempool.h
+++ /dev/null
@@ -1,65 +0,0 @@
-/* Copyright (c) 2007-2015, The Tor Project, Inc. */
-/* See LICENSE for licensing information */
-
-/**
- * \file mempool.h
- * \brief Headers for mempool.c
- **/
-
-#ifndef TOR_MEMPOOL_H
-#define TOR_MEMPOOL_H
-
-/** A memory pool is a context in which a large number of fixed-sized
-* objects can be allocated efficiently.  See mempool.c for implementation
-* details. */
-typedef struct mp_pool_t mp_pool_t;
-
-void *mp_pool_get(mp_pool_t *pool);
-void mp_pool_release(void *item);
-mp_pool_t *mp_pool_new(size_t item_size, size_t chunk_capacity);
-void mp_pool_clean(mp_pool_t *pool, int n_to_keep, int keep_recently_used);
-void mp_pool_destroy(mp_pool_t *pool);
-void mp_pool_assert_ok(mp_pool_t *pool);
-void mp_pool_log_status(mp_pool_t *pool, int severity);
-
-#define MP_POOL_ITEM_OVERHEAD (sizeof(void*))
-
-#define MEMPOOL_STATS
-
-#ifdef MEMPOOL_PRIVATE
-/* These declarations are only used by mempool.c and test.c */
-
-struct mp_pool_t {
-  /** Doubly-linked list of chunks in which no items have been allocated.
-   * The front of the list is the most recently emptied chunk. */
-  struct mp_chunk_t *empty_chunks;
-  /** Doubly-linked list of chunks in which some items have been allocated,
-   * but which are not yet full. The front of the list is the chunk that has
-   * most recently been modified. */
-  struct mp_chunk_t *used_chunks;
-  /** Doubly-linked list of chunks in which no more items can be allocated.
-   * The front of the list is the chunk that has most recently become full. */
-  struct mp_chunk_t *full_chunks;
-  /** Length of <b>empty_chunks</b>. */
-  int n_empty_chunks;
-  /** Lowest value of <b>empty_chunks</b> since last call to
-   * mp_pool_clean(-1). */
-  int min_empty_chunks;
-  /** Size of each chunk (in items). */
-  int new_chunk_capacity;
-  /** Size to allocate for each item, including overhead and alignment
-   * padding. */
-  size_t item_alloc_size;
-#ifdef MEMPOOL_STATS
-  /** Total number of items allocated ever. */
-  uint64_t total_items_allocated;
-  /** Total number of chunks allocated ever. */
-  uint64_t total_chunks_allocated;
-  /** Total number of chunks freed ever. */
-  uint64_t total_chunks_freed;
-#endif
-};
-#endif
-
-#endif
-
diff --git a/src/or/buffers.c b/src/or/buffers.c
index ca0e815e33..9f5dc70ed5 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -105,114 +105,6 @@ chunk_repack(chunk_t *chunk)
 
 /** Keep track of total size of allocated chunks for consistency asserts */
 static size_t total_bytes_allocated_in_chunks = 0;
-
-#if defined(ENABLE_BUF_FREELISTS) || defined(RUNNING_DOXYGEN)
-/** A freelist of chunks. */
-typedef struct chunk_freelist_t {
-  size_t alloc_size; /**< What size chunks does this freelist hold? */
-  int max_length; /**< Never allow more than this number of chunks in the
-                   * freelist. */
-  int slack; /**< When trimming the freelist, leave this number of extra
-              * chunks beyond lowest_length.*/
-  int cur_length; /**< How many chunks on the freelist now? */
-  int lowest_length; /**< What's the smallest value of cur_length since the
-                      * last time we cleaned this freelist? */
-  uint64_t n_alloc;
-  uint64_t n_free;
-  uint64_t n_hit;
-  chunk_t *head; /**< First chunk on the freelist. */
-} chunk_freelist_t;
-
-/** Macro to help define freelists. */
-#define FL(a,m,s) { a, m, s, 0, 0, 0, 0, 0, NULL }
-
-/** Static array of freelists, sorted by alloc_len, terminated by an entry
- * with alloc_size of 0. */
-static chunk_freelist_t freelists[] = {
-  FL(4096, 256, 8), FL(8192, 128, 4), FL(16384, 64, 4), FL(32768, 32, 2),
-  FL(0, 0, 0)
-};
-#undef FL
-/** How many times have we looked for a chunk of a size that no freelist
- * could help with? */
-static uint64_t n_freelist_miss = 0;
-
-static void assert_freelist_ok(chunk_freelist_t *fl);
-
-/** Return the freelist to hold chunks of size <b>alloc</b>, or NULL if
- * no freelist exists for that size. */
-static INLINE chunk_freelist_t *
-get_freelist(size_t alloc)
-{
-  int i;
-  for (i=0; (freelists[i].alloc_size <= alloc &&
-             freelists[i].alloc_size); ++i ) {
-    if (freelists[i].alloc_size == alloc) {
-      return &freelists[i];
-    }
-  }
-  return NULL;
-}
-
-/** Deallocate a chunk or put it on a freelist */
-static void
-chunk_free_unchecked(chunk_t *chunk)
-{
-  size_t alloc;
-  chunk_freelist_t *freelist;
-
-  alloc = CHUNK_ALLOC_SIZE(chunk->memlen);
-  freelist = get_freelist(alloc);
-  if (freelist && freelist->cur_length < freelist->max_length) {
-    chunk->next = freelist->head;
-    freelist->head = chunk;
-    ++freelist->cur_length;
-  } else {
-    if (freelist)
-      ++freelist->n_free;
-#ifdef DEBUG_CHUNK_ALLOC
-    tor_assert(alloc  == chunk->DBG_alloc);
-#endif
-    tor_assert(total_bytes_allocated_in_chunks >= alloc);
-    total_bytes_allocated_in_chunks -= alloc;
-    tor_free(chunk);
-  }
-}
-
-/** Allocate a new chunk with a given allocation size, or get one from the
- * freelist.  Note that a chunk with allocation size A can actually hold only
- * CHUNK_SIZE_WITH_ALLOC(A) bytes in its mem field. */
-static INLINE chunk_t *
-chunk_new_with_alloc_size(size_t alloc)
-{
-  chunk_t *ch;
-  chunk_freelist_t *freelist;
-  tor_assert(alloc >= sizeof(chunk_t));
-  freelist = get_freelist(alloc);
-  if (freelist && freelist->head) {
-    ch = freelist->head;
-    freelist->head = ch->next;
-    if (--freelist->cur_length < freelist->lowest_length)
-      freelist->lowest_length = freelist->cur_length;
-    ++freelist->n_hit;
-  } else {
-    if (freelist)
-      ++freelist->n_alloc;
-    else
-      ++n_freelist_miss;
-    ch = tor_malloc(alloc);
-#ifdef DEBUG_CHUNK_ALLOC
-    ch->DBG_alloc = alloc;
-#endif
-    total_bytes_allocated_in_chunks += alloc;
-  }
-  ch->next = NULL;
-  ch->datalen = 0;
-  ch->memlen = CHUNK_SIZE_WITH_ALLOC(alloc);
-  ch->data = &ch->mem[0];
-  return ch;
-}
-#else
 static void
 chunk_free_unchecked(chunk_t *chunk)
 {
@@ -241,7 +133,6 @@ chunk_new_with_alloc_size(size_t alloc)
   ch->data = &ch->mem[0];
   return ch;
 }
-#endif
 
 /** Expand <b>chunk</b> until it can hold <b>sz</b> bytes, and return a
  * new pointer to <b>chunk</b>.  Old pointers are no longer valid. */
@@ -284,115 +175,6 @@ preferred_chunk_size(size_t target)
   return sz;
 }
 
-/** Remove from the freelists most chunks that have not been used since the
- * last call to buf_shrink_freelists().   Return the amount of memory
- * freed. */
-size_t
-buf_shrink_freelists(int free_all)
-{
-#ifdef ENABLE_BUF_FREELISTS
-  int i;
-  size_t total_freed = 0;
-  disable_control_logging();
-  for (i = 0; freelists[i].alloc_size; ++i) {
-    int slack = freelists[i].slack;
-    assert_freelist_ok(&freelists[i]);
-    if (free_all || freelists[i].lowest_length > slack) {
-      int n_to_free = free_all ? freelists[i].cur_length :
-        (freelists[i].lowest_length - slack);
-      int n_to_skip = freelists[i].cur_length - n_to_free;
-      int orig_length = freelists[i].cur_length;
-      int orig_n_to_free = n_to_free, n_freed=0;
-      int orig_n_to_skip = n_to_skip;
-      int new_length = n_to_skip;
-      chunk_t **chp = &freelists[i].head;
-      chunk_t *chunk;
-      while (n_to_skip) {
-        if (!(*chp) || ! (*chp)->next) {
-          log_warn(LD_BUG, "I wanted to skip %d chunks in the freelist for "
-                   "%d-byte chunks, but only found %d. (Length %d)",
-                   orig_n_to_skip, (int)freelists[i].alloc_size,
-                   orig_n_to_skip-n_to_skip, freelists[i].cur_length);
-          assert_freelist_ok(&freelists[i]);
-          goto done;
-        }
-        // tor_assert((*chp)->next);
-        chp = &(*chp)->next;
-        --n_to_skip;
-      }
-      chunk = *chp;
-      *chp = NULL;
-      while (chunk) {
-        chunk_t *next = chunk->next;
-#ifdef DEBUG_CHUNK_ALLOC
-        tor_assert(chunk->DBG_alloc == CHUNK_ALLOC_SIZE(chunk->memlen));
-#endif
-        tor_assert(total_bytes_allocated_in_chunks >=
-                   CHUNK_ALLOC_SIZE(chunk->memlen));
-        total_bytes_allocated_in_chunks -= CHUNK_ALLOC_SIZE(chunk->memlen);
-        total_freed += CHUNK_ALLOC_SIZE(chunk->memlen);
-        tor_free(chunk);
-        chunk = next;
-        --n_to_free;
-        ++n_freed;
-        ++freelists[i].n_free;
-      }
-      if (n_to_free) {
-        log_warn(LD_BUG, "Freelist length for %d-byte chunks may have been "
-                 "messed up somehow.", (int)freelists[i].alloc_size);
-        log_warn(LD_BUG, "There were %d chunks at the start.  I decided to "
-                 "keep %d. I wanted to free %d.  I freed %d.  I somehow think "
-                 "I have %d left to free.",
-                 freelists[i].cur_length, n_to_skip, orig_n_to_free,
-                 n_freed, n_to_free);
-      }
-      // tor_assert(!n_to_free);
-      freelists[i].cur_length = new_length;
-      tor_assert(orig_n_to_skip == new_length);
-      log_info(LD_MM, "Cleaned freelist for %d-byte chunks: original "
-               "length %d, kept %d, dropped %d. New length is %d",
-               (int)freelists[i].alloc_size, orig_length,
-               orig_n_to_skip, orig_n_to_free, new_length);
-    }
-    freelists[i].lowest_length = freelists[i].cur_length;
-    assert_freelist_ok(&freelists[i]);
-  }
- done:
-  enable_control_logging();
-  return total_freed;
-#else
-  (void) free_all;
-  return 0;
-#endif
-}
-
-/** Describe the current status of the freelists at log level <b>severity</b>.
- */
-void
-buf_dump_freelist_sizes(int severity)
-{
-#ifdef ENABLE_BUF_FREELISTS
-  int i;
-  tor_log(severity, LD_MM, "====== Buffer freelists:");
-  for (i = 0; freelists[i].alloc_size; ++i) {
-    uint64_t total = ((uint64_t)freelists[i].cur_length) *
-      freelists[i].alloc_size;
-    tor_log(severity, LD_MM,
-        U64_FORMAT" bytes in %d %d-byte chunks ["U64_FORMAT
-        " misses; "U64_FORMAT" frees; "U64_FORMAT" hits]",
-        U64_PRINTF_ARG(total),
-        freelists[i].cur_length, (int)freelists[i].alloc_size,
-        U64_PRINTF_ARG(freelists[i].n_alloc),
-        U64_PRINTF_ARG(freelists[i].n_free),
-        U64_PRINTF_ARG(freelists[i].n_hit));
-  }
-  tor_log(severity, LD_MM, U64_FORMAT" allocations in non-freelist sizes",
-      U64_PRINTF_ARG(n_freelist_miss));
-#else
-  (void)severity;
-#endif
-}
-
 /** Collapse data from the first N chunks from <b>buf</b> into buf->head,
  * growing it as necessary, until buf->head has the first <b>bytes</b> bytes
  * of data from the buffer, or until buf->head has all the data in <b>buf</b>.
@@ -488,15 +270,6 @@ buf_get_first_chunk_data(const buf_t *buf, const char **cp, size_t *sz)
 }
 #endif
 
-/** Resize buf so it won't hold extra memory that we haven't been
- * using lately.
- */
-void
-buf_shrink(buf_t *buf)
-{
-  (void)buf;
-}
-
 /** Remove the first <b>n</b> bytes from buf. */
 static INLINE void
 buf_remove_from_front(buf_t *buf, size_t n)
@@ -2672,23 +2445,3 @@ assert_buf_ok(buf_t *buf)
   }
 }
 
-#ifdef ENABLE_BUF_FREELISTS
-/** Log an error and exit if <b>fl</b> is corrupted.
- */
-static void
-assert_freelist_ok(chunk_freelist_t *fl)
-{
-  chunk_t *ch;
-  int n;
-  tor_assert(fl->alloc_size > 0);
-  n = 0;
-  for (ch = fl->head; ch; ch = ch->next) {
-    tor_assert(CHUNK_ALLOC_SIZE(ch->memlen) == fl->alloc_size);
-    ++n;
-  }
-  tor_assert(n == fl->cur_length);
-  tor_assert(n >= fl->lowest_length);
-  tor_assert(n <= fl->max_length);
-}
-#endif
-
diff --git a/src/or/buffers.h b/src/or/buffers.h
index 6dd3d1762b..6d0c68500b 100644
--- a/src/or/buffers.h
+++ b/src/or/buffers.h
@@ -20,9 +20,6 @@ size_t buf_get_default_chunk_size(const buf_t *buf);
 void buf_free(buf_t *buf);
 void buf_clear(buf_t *buf);
 buf_t *buf_copy(const buf_t *buf);
-void buf_shrink(buf_t *buf);
-size_t buf_shrink_freelists(int free_all);
-void buf_dump_freelist_sizes(int severity);
 
 MOCK_DECL(size_t, buf_datalen, (const buf_t *buf));
 size_t buf_allocation(const buf_t *buf);
@@ -108,9 +105,9 @@ STATIC void buf_pullup(buf_t *buf, size_t bytes, int nulterminate);
 void buf_get_first_chunk_data(const buf_t *buf, const char **cp, size_t *sz);
 
 #define DEBUG_CHUNK_ALLOC
-/** A single chunk on a buffer or in a freelist. */
+/** A single chunk on a buffer. */
 typedef struct chunk_t {
-  struct chunk_t *next; /**< The next chunk on the buffer or freelist. */
+  struct chunk_t *next; /**< The next chunk on the buffer. */
   size_t datalen; /**< The number of bytes stored in this chunk */
   size_t memlen; /**< The number of usable bytes of storage in <b>mem</b>. */
 #ifdef DEBUG_CHUNK_ALLOC
diff --git a/src/or/circuitlist.c b/src/or/circuitlist.c
index d964e66922..5355b17c1d 100644
--- a/src/or/circuitlist.c
+++ b/src/or/circuitlist.c
@@ -2063,17 +2063,6 @@ circuits_handle_oom(size_t current_allocation)
              "MaxMemInQueues.)");
 
   {
-    const size_t recovered = buf_shrink_freelists(1);
-    if (recovered >= current_allocation) {
-      log_warn(LD_BUG, "We somehow recovered more memory from freelists "
-               "than we thought we had allocated");
-      current_allocation = 0;
-    } else {
-      current_allocation -= recovered;
-    }
-  }
-
-  {
     size_t mem_target = (size_t)(get_options()->MaxMemInQueues *
                                  FRACTION_OF_DATA_TO_RETAIN_ON_OOM);
     if (current_allocation <= mem_target)
@@ -2156,12 +2145,6 @@ circuits_handle_oom(size_t current_allocation)
 
  done_recovering_mem:
 
-#ifdef ENABLE_MEMPOOLS
-  clean_cell_pool(); /* In case this helps. */
-#endif /* ENABLE_MEMPOOLS */
-  buf_shrink_freelists(1); /* This is necessary to actually release buffer
-                              chunks. */
-
   log_notice(LD_GENERAL, "Removed "U64_FORMAT" bytes by killing %d circuits; "
              "%d circuits remain alive. Also killed %d non-linked directory "
              "connections.",
diff --git a/src/or/main.c b/src/or/main.c
index 136043c117..09144cb1fb 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -1223,7 +1223,6 @@ run_scheduled_events(time_t now)
   static time_t time_to_check_v3_certificate = 0;
   static time_t time_to_check_listeners = 0;
   static time_t time_to_download_networkstatus = 0;
-  static time_t time_to_shrink_memory = 0;
   static time_t time_to_try_getting_descriptors = 0;
   static time_t time_to_reset_descriptor_failures = 0;
   static time_t time_to_add_entropy = 0;
@@ -1573,22 +1572,6 @@ run_scheduled_events(time_t now)
   for (i=0;i<smartlist_len(connection_array);i++) {
     run_connection_housekeeping(i, now);
   }
-  if (time_to_shrink_memory < now) {
-    SMARTLIST_FOREACH(connection_array, connection_t *, conn, {
-        if (conn->outbuf)
-          buf_shrink(conn->outbuf);
-        if (conn->inbuf)
-          buf_shrink(conn->inbuf);
-      });
-#ifdef ENABLE_MEMPOOL
-    clean_cell_pool();
-#endif /* ENABLE_MEMPOOL */
-    buf_shrink_freelists(0);
-/** How often do we check buffers and pools for empty space that can be
- * deallocated? */
-#define MEM_SHRINK_INTERVAL (60)
-    time_to_shrink_memory = now + MEM_SHRINK_INTERVAL;
-  }
 
   /* 6. And remove any marked circuits... */
   circuit_close_all_marked();
@@ -2260,7 +2243,6 @@ dumpmemusage(int severity)
   dump_routerlist_mem_usage(severity);
   dump_cell_pool_usage(severity);
   dump_dns_mem_usage(severity);
-  buf_dump_freelist_sizes(severity);
   tor_log_mallinfo(severity);
 }
 
@@ -2652,7 +2634,6 @@ tor_free_all(int postfork)
   channel_free_all();
   connection_free_all();
   scheduler_free_all();
-  buf_shrink_freelists(1);
   memarea_clear_freelist();
   nodelist_free_all();
   microdesc_free_all();
diff --git a/src/test/test_buffers.c b/src/test/test_buffers.c
index 101f448472..0ede8081d8 100644
--- a/src/test/test_buffers.c
+++ b/src/test/test_buffers.c
@@ -193,7 +193,6 @@ test_buffers_basic(void *arg)
     buf_free(buf);
   if (buf2)
     buf_free(buf2);
-  buf_shrink_freelists(1);
 }
 
 static void
@@ -297,12 +296,9 @@ test_buffer_pullup(void *arg)
   buf_free(buf);
   buf = NULL;
 
-  buf_shrink_freelists(1);
-
   tt_int_op(buf_get_total_allocation(), OP_EQ, 0);
  done:
   buf_free(buf);
-  buf_shrink_freelists(1);
   tor_free(stuff);
   tor_free(tmp);
 }
@@ -370,7 +366,6 @@ test_buffer_copy(void *arg)
     generic_buffer_free(buf);
   if (buf2)
     generic_buffer_free(buf2);
-  buf_shrink_freelists(1);
 }
 
 static void
@@ -445,7 +440,6 @@ test_buffer_ext_or_cmd(void *arg)
   ext_or_cmd_free(cmd);
   generic_buffer_free(buf);
   tor_free(tmp);
-  buf_shrink_freelists(1);
 }
 
 static void
@@ -481,20 +475,13 @@ test_buffer_allocation_tracking(void *arg)
   fetch_from_buf(junk, 4096, buf1); /* drop a 1k chunk... */
   tt_int_op(buf_allocation(buf1), OP_EQ, 3*4096); /* now 3 4k chunks */
 
-#ifdef ENABLE_BUF_FREELISTS
-  tt_int_op(buf_get_total_allocation(), OP_EQ, 16384); /* that chunk went onto
-                                                       the freelist. */
-#else
   tt_int_op(buf_get_total_allocation(), OP_EQ, 12288); /* that chunk was really
                                                        freed. */
-#endif
 
   write_to_buf(junk, 4000, buf2);
   tt_int_op(buf_allocation(buf2), OP_EQ, 4096); /* another 4k chunk. */
   /*
-   * If we're using freelists, size stays at 16384 because we just pulled a
-   * chunk from the freelist.  If we aren't, we bounce back up to 16384 by
-   * allocating a new chunk.
+   * We bounce back up to 16384 by allocating a new chunk.
    */
   tt_int_op(buf_get_total_allocation(), OP_EQ, 16384);
   write_to_buf(junk, 4000, buf2);
@@ -512,17 +499,14 @@ test_buffer_allocation_tracking(void *arg)
   buf2 = NULL;
 
   tt_int_op(buf_get_total_allocation(), OP_LT, 4008000);
-  buf_shrink_freelists(1);
   tt_int_op(buf_get_total_allocation(), OP_EQ, buf_allocation(buf1));
   buf_free(buf1);
   buf1 = NULL;
-  buf_shrink_freelists(1);
   tt_int_op(buf_get_total_allocation(), OP_EQ, 0);
 
  done:
   buf_free(buf1);
   buf_free(buf2);
-  buf_shrink_freelists(1);
   tor_free(junk);
 }
 
diff --git a/src/test/test_util.c b/src/test/test_util.c
index e5df5b4494..9939bf4e3e 100644
--- a/src/test/test_util.c
+++ b/src/test/test_util.c
@@ -6,15 +6,11 @@
 #include "orconfig.h"
 #define COMPAT_PRIVATE
 #define CONTROL_PRIVATE
-#define MEMPOOL_PRIVATE
 #define UTIL_PRIVATE
 #include "or.h"
 #include "config.h"
 #include "control.h"
 #include "test.h"
-#ifdef ENABLE_MEMPOOLS
-#include "mempool.h"
-#endif /* ENABLE_MEMPOOLS */
 #include "memarea.h"
 #include "util_process.h"
 
@@ -2644,69 +2640,6 @@ test_util_path_is_relative(void *arg)
   ;
 }
 
-#ifdef ENABLE_MEMPOOLS
-
-/** Run unittests for memory pool allocator */
-static void
-test_util_mempool(void *arg)
-{
-  mp_pool_t *pool = NULL;
-  smartlist_t *allocated = NULL;
-  int i;
-
-  (void)arg;
-  pool = mp_pool_new(1, 100);
-  tt_assert(pool);
-  tt_assert(pool->new_chunk_capacity >= 100);
-  tt_assert(pool->item_alloc_size >= sizeof(void*)+1);
-  mp_pool_destroy(pool);
-  pool = NULL;
-
-  pool = mp_pool_new(241, 2500);
-  tt_assert(pool);
-  tt_assert(pool->new_chunk_capacity >= 10);
-  tt_assert(pool->item_alloc_size >= sizeof(void*)+241);
-  tt_int_op(pool->item_alloc_size & 0x03,OP_EQ, 0);
-  tt_assert(pool->new_chunk_capacity < 60);
-
-  allocated = smartlist_new();
-  for (i = 0; i < 20000; ++i) {
-    if (smartlist_len(allocated) < 20 || crypto_rand_int(2)) {
-      void *m = mp_pool_get(pool);
-      memset(m, 0x09, 241);
-      smartlist_add(allocated, m);
-      //printf("%d: %p\n", i, m);
-      //mp_pool_assert_ok(pool);
-    } else {
-      int idx = crypto_rand_int(smartlist_len(allocated));
-      void *m = smartlist_get(allocated, idx);
-      //printf("%d: free %p\n", i, m);
-      smartlist_del(allocated, idx);
-      mp_pool_release(m);
-      //mp_pool_assert_ok(pool);
-    }
-    if (crypto_rand_int(777)==0)
-      mp_pool_clean(pool, 1, 1);
-
-    if (i % 777)
-      mp_pool_assert_ok(pool);
-  }
-
- done:
-  if (allocated) {
-    SMARTLIST_FOREACH(allocated, void *, m, mp_pool_release(m));
-    mp_pool_assert_ok(pool);
-    mp_pool_clean(pool, 0, 0);
-    mp_pool_assert_ok(pool);
-    smartlist_free(allocated);
-  }
-
-  if (pool)
-    mp_pool_destroy(pool);
-}
-
-#endif /* ENABLE_MEMPOOLS */
-
 /** Run unittests for memory area allocator */
 static void
 test_util_memarea(void *arg)