)]}'
{
  "commit": "10660c0131fbccaab609fca4aad9a134ebe20adc",
  "tree": "a080bb04ef8eca0462b0567e266a60e4bb5effcf",
  "parents": [
    "64b973d73840e22b35999e87ee4e885dc280171e"
  ],
  "author": {
    "name": "He Gao",
    "email": "hegao@google.com",
    "time": "Mon Oct 20 18:25:01 2025 +0000"
  },
  "committer": {
    "name": "Cloud Image Release",
    "email": "cloud-image-release@prod.google.com",
    "time": "Mon Nov 03 15:03:47 2025 -0800"
  },
  "message": "bcache: add \"clock\" cache replacement policy\n\n@ 2025-10-09  7:15 Robert Pang\n  2025-10-09 22:06 ` Robert Pang\n  0 siblings, 1 reply; 2+ messages in thread\nFrom: Robert Pang @ 2025-10-09  7:15 UTC (permalink / raw)\n  To: Coly Li, Kent Overstreet; +Cc: linux-bcache, linux-kernel, Robert Pang\n\nThis new policy extends the FIFO policy to approximate the classic clock policy\n(O(n) time complexity) by considering bucket priority, similar to the LRU\npolicy.\n\nThis clock policy addresses the high IO latency (1-2 seconds) experienced on\nmulti-terabyte cache devices when the free list is empty due to the default LRU\npolicy. The LRU policy\u0027s O(n log n) complexity for sorting priorities for the\nentire bucket list causes this delay.\n\nHere are the average execution times (in microseconds) of the LRU and the clock\nreplacement policies:\n\nSSD Size  Bucket Count  LRU (us)  Clock (us)\n375 GB      1536000       58292        1163\n750 GB      3072000      121769        1729\n1.5 TB      6144000      244012        3862\n3 TB       12288000      496569        6428\n6 TB       24576000     1067628       14298\n9 TB       36864000     1564348       25763\n\nBUG\u003db/452726527\nTEST\u003dpresubmit\nRELEASE_NOTE\u003dFixed bcache latency spikes.\n\ncos-patch: bug\nChange-Id: I29cc6ebd98f163fca95053e611a2b2656d654653\nSigned-off-by: Robert Pang \u003crobertpang@google.com\u003e\nReviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/114884\nReviewed-by: Robert Kolchmeyer \u003crkolchmeyer@google.com\u003e\nMain-Branch-Verified: Cusky Presubmit Bot \u003cpresubmit@cos-infra-prod.iam.gserviceaccount.com\u003e\nTested-by: Cusky Presubmit Bot \u003cpresubmit@cos-infra-prod.iam.gserviceaccount.com\u003e\nReviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/116804\n",
  "tree_diff": [
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    },
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      "old_mode": 33188,
      "old_path": "drivers/md/bcache/bcache_ondisk.h",
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      "new_mode": 33188,
      "new_path": "drivers/md/bcache/bcache_ondisk.h"
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      "old_mode": 33188,
      "old_path": "drivers/md/bcache/sysfs.c",
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}