bmalloc: small and large objects should share memory
Created attachment 274876 [details] Patch
Memory: ~/OpenSource/PerformanceTests/MallocBench> ./run-malloc-benchmarks --memory_warning Baseline:~/OpenSource/WebKitBuildBaseline/Release/ Patch:~/OpenSource/WebKitBuild/Release/ Baseline Patch Δ Peak Memory: reddit_memory_warning --runs 0 13,064kB 13,152kB ! 1.01x bigger flickr_memory_warning --runs 0 24,264kB 23,528kB ^ 1.03x smaller theverge_memory_warning --runs 0 26,080kB 25,488kB ^ 1.02x smaller <geometric mean> 20,220kB 19,905kB ^ 1.02x smaller <arithmetic mean> 21,136kB 20,723kB ^ 1.02x smaller <harmonic mean> 19,218kB 19,015kB ^ 1.01x smaller Memory at End: reddit_memory_warning --runs 0 8,720kB 8,708kB ^ 1.0x smaller flickr_memory_warning --runs 0 11,772kB 11,860kB ! 1.01x bigger theverge_memory_warning --runs 0 20,652kB 20,644kB ^ 1.0x smaller <geometric mean> 12,846kB 12,871kB ! 1.0x bigger <arithmetic mean> 13,715kB 13,737kB ! 1.0x bigger <harmonic mean> 12,094kB 12,117kB ! 1.0x bigger ~/OpenSource/PerformanceTests/MallocBench> ./run-malloc-benchmarks --memory Baseline:~/OpenSource/WebKitBuildBaseline/Release/ Patch:~/OpenSource/WebKitBuild/Release/ Baseline Patch Δ Peak Memory: facebook 73,008kB 74,000kB ! 1.01x bigger reddit 13,116kB 13,236kB ! 1.01x bigger flickr 24,584kB 23,384kB ^ 1.05x smaller theverge 26,112kB 25,544kB ^ 1.02x smaller <geometric mean> 28,001kB 27,657kB ^ 1.01x smaller <arithmetic mean> 34,205kB 34,041kB ^ 1.0x smaller <harmonic mean> 23,681kB 23,395kB ^ 1.01x smaller Memory at End: facebook 2,716kB 3,328kB ! 1.23x bigger reddit 1,732kB 1,780kB ! 1.03x bigger flickr 2,744kB 2,808kB ! 1.02x bigger theverge 2,800kB 2,896kB ! 1.03x bigger <geometric mean> 2,452kB 2,635kB ! 1.07x bigger <arithmetic mean> 2,498kB 2,703kB ! 1.08x bigger <harmonic mean> 2,399kB 2,558kB ! 1.07x bigger Memory at end goes up because of our extra metadata. (We don't free metadata.) I think this is worth it because of the other benefits in this patch -- but I'm going to try to reduce or free metadata in a follow-up patch.
Throughput: ~/OpenSource/PerformanceTests/MallocBench> ./run-malloc-benchmarks Baseline:~/OpenSource/WebKitBuildBaseline/Release/ Patch:~/OpenSource/WebKitBuild/Release/ Baseline Patch Δ Execution Time: churn 76ms 74ms ^ 1.03x faster list_allocate 71ms 70ms ^ 1.01x faster tree_allocate 72ms 73ms ! 1.01x slower tree_churn 79ms 80ms ! 1.01x slower fragment 131ms 132ms ! 1.01x slower fragment_iterate 76ms 76ms medium 191ms 174ms ^ 1.1x faster big 138ms 137ms ^ 1.01x faster facebook 221ms 231ms ! 1.05x slower reddit 111ms 114ms ! 1.03x slower flickr 115ms 119ms ! 1.03x slower theverge 144ms 147ms ! 1.02x slower nimlang 118ms 122ms ! 1.03x slower message_one 205ms 209ms ! 1.02x slower message_many 113ms 113ms churn --parallel 37ms 36ms ^ 1.03x faster list_allocate --parallel 65ms 62ms ^ 1.05x faster tree_allocate --parallel 75ms 76ms ! 1.01x slower tree_churn --parallel 85ms 83ms ^ 1.02x faster fragment --parallel 94ms 94ms fragment_iterate --parallel 31ms 31ms medium --parallel 182ms 177ms ^ 1.03x faster big --parallel 129ms 130ms ! 1.01x slower <geometric mean> 100ms 100ms ^ 1.0x faster <arithmetic mean> 111ms 111ms ! 1.0x slower <harmonic mean> 88ms 87ms ^ 1.0x faster
Created attachment 274877 [details] Patch
Some stress tests are hit particularly hard by the extra metadata: Memory at End: medium 4,600kB 15,076kB ! 3.28x bigger big 4,584kB 15,024kB ! 3.28x bigger fragment --parallel 880kB 1,956kB ! 2.22x bigger medium --parallel 4,712kB 19,856kB ! 4.21x bigger big --parallel 4,700kB 38,284kB ! 8.15x bigger medium and big start out with 1GB heaps and then shrink to 0, so they're more of a stress test than a benchmark of memory use in the mean.
Created attachment 274878 [details] Patch
Created attachment 274909 [details] Patch
Comment on attachment 274909 [details] Patch r=me
Committed r198675: <http://trac.webkit.org/changeset/198675>