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There were 264 callbacks in the trace:   callback elapsed time:     median:    5.77 ms     p95:      55.82 ms     maximum: 271.36 ms   compactable ratio before compaction:     median:   0.32%     p95:      2.86%     maximum:  8.33%   memory reclaimed per callback:     median:    3.80 MiB     p95:      30.45 MiB     maximum:  92.73 MiB The longest callback took 271.36 ms. Its compactable ratio was 3.25%, and it released 7,650 pages, or about 29.88 MiB. There was also a 241.91 ms callback (with 30 schedule-outs) with a compactable ratio of 0.44%. It released 1,019 pages, or about 3.98 MiB. Based on this data, it seems better to remove the shrinker. Would you prefer that I change v2 to remove the zsmalloc shrinker callbacks directly? Thanks, Xueyuan On 8/7/2026 11:56 AM, Sergey Senozhatsky wrote: > On (26/08/06 16:27), xueyuan.chen@vivo.com wrote: >> On an Android device with 12 GB of RAM, observed zsmalloc compaction >> durations had a p95 of 38.86 ms and a maximum of 269.68 ms, motivating a >> per-scan reclaim goal. > Would it be possible to give a little more data? What was the > fragmentation ratio, how much memory was saved during that > auto-compaction, etc. If possible. > > Somewhere in the back of my mind I was thinking about, maybe, > disabling (removing) zsmalloc shrinker callbacks, in other words > disabling auto-compaction. We have a sysfs knob for pool compaction > for system that still want to run compaction. So I'm leaning towards > removal of shrinker callbacks from zsmalloc.