Commit Graph

12 Commits

Author SHA1 Message Date
David Goldblatt
181093173d Tcache: make slot sizing configurable. 2020-05-16 13:34:23 -07:00
David Goldblatt
d701a085c2 Fast path: allow low-water mark changes.
This lets us put more allocations on an "almost as fast" path after a flush.
This results in around a 4% reduction in malloc cycles in prod workloads
(corresponding to about a 0.1% reduction in overall cycles).
2020-03-12 11:54:19 -07:00
David Goldblatt
370c1ea007 Cache bin: Write the unit test in terms of the API
I.e. stop allowing the unit test to have secret access to implementation
internals.
2020-03-12 11:54:19 -07:00
David Goldblatt
ff6acc6ed5 Cache bin: simplify names and argument ordering.
We always start with the cache bin, then its info (if necessary).
2020-03-12 11:54:19 -07:00
David Goldblatt
e1dcc557d6 Cache bin: Only take the relevant cache_bin_info_t
Previously, we took an array of cache_bin_info_ts and an index, and dereferenced
ourselves.  But infos for other cache_bins aren't relevant to any particular
cache bin, so that should be the caller's job.
2020-03-12 11:54:19 -07:00
David Goldblatt
74d36d78ef Cache bin: Make ncached_max a query on the info_t. 2020-03-12 11:54:19 -07:00
David Goldblatt
909c501b07 Cache_bin: Shouldn't know about tcache.
Instead, have it take the cache_bin_info_ts to use by pointer.  While we're
here, add a src file for the cache bin.
2020-03-12 11:54:19 -07:00
Yinan Zhang
21dfa4300d Change assert_* to expect_* in tests
```
grep -Irl assert_ test/ | xargs sed -i \
    's/witness_assert/witness_do_not_replace/g';
grep -Irl assert_ test/ | xargs sed -i \
    's/malloc_mutex_assert_owner/malloc_mutex_do_not_replace_owner/g';

grep -Ir assert_ test/ | grep -o "[_a-zA-Z]*assert_[_a-zA-Z]*" | \
    grep -v "^assert_"; # confirm no output
grep -Irl assert_ test/ | xargs sed -i 's/assert_/expect_/g';

grep -Irl witness_do_not_replace test/ | xargs sed -i \
    's/witness_do_not_replace/witness_assert/g';
grep -Irl malloc_mutex_do_not_replace_owner test/ | xargs sed -i \
    's/malloc_mutex_do_not_replace_owner/malloc_mutex_assert_owner/g';
```
2020-02-19 16:03:16 -08:00
Qi Wang
1decf958d1 Fix incorrect usage of cassert. 2019-12-11 14:02:59 -08:00
Qi Wang
0043e68d4c Track low_water == -1 case explicitly.
The -1 value of low_water indicates if the cache has been depleted and
refilled.  Track the status explicitly in the tcache struct.

This allows the fast path to check if (cur_ptr > low_water), instead of >=,
which avoids reaching slow path when the last item is allocated.
2019-08-21 16:00:38 -07:00
Qi Wang
937ca1db9f Store ncached_max * ptr_size in tcache_bin_info.
With the cache bin metadata switched to pointers, ncached_max is usually
accessed and timed by sizeof(ptr). Store the results in tcache_bin_info for
direct access, and add a helper function for the ncached_max value.
2019-08-19 12:23:24 -07:00
Qi Wang
7599c82d48 Redesign the cache bin metadata for fast path.
Implement the pointer-based metadata for tcache bins --
- 3 pointers are maintained to represent each bin;
- 2 of the pointers are compressed on 64-bit;
- is_full / is_empty done through pointer comparison;

Comparing to the previous counter based design --
- fast-path speed up ~15% in benchmarks
- direct pointer comparison and de-reference
- no need to access tcache_bin_info in common case
2019-08-19 12:21:44 -07:00