WT-15766 Skip readonly btree for checkpoint by whoisong · Pull Request #13239 · wiredtiger/wiredtiger

whoisong · 2026-02-23T04:22:20Z

Read-only B-trees use relaxed concurrency that can race with checkpoint and cause failures. To avoid these races, this PR skips read-only B-trees during checkpoint processing.

github-actions · 2026-02-23T04:22:29Z

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quchenhao · 2026-02-23T04:26:47Z

src/conn/conn_stat.c

     */
    if (conn->stat_sources != NULL && F_ISSET(conn, WT_CONN_RECOVERY_COMPLETE))
-        WT_RET(__wt_conn_btree_apply(session, NULL, __statlog_apply, NULL, NULL));
+        WT_RET(__wt_conn_btree_apply(session, false, NULL, __statlog_apply, NULL, NULL));


There is also no point gathering stats for read only btree.

Talked with @bvpvamsikrishna and in case we'll need this in debugging scenarios, we shouldn't disable it globally. But I'll take the suggestion of skip_read.

quchenhao · 2026-02-23T04:27:08Z

src/conn/conn_dhandle.c

                continue;

+            /*
+             * We should skip readonly btrees during checkpoint scans.


single line comment

quchenhao · 2026-02-23T04:27:36Z

src/conn/conn_dhandle.c

 */
 int
-__wt_conn_btree_apply(WT_SESSION_IMPL *session, const char *uri,
+__wt_conn_btree_apply(WT_SESSION_IMPL *session, bool is_checkpoint, const char *uri,


rename this to bool skip_read only?

ddanderson

Here's a different approach to consider, maybe cleaner. LMKWYT

ddanderson · 2026-02-23T04:50:45Z

src/conn/conn_dhandle.c

 */
 int
-__wt_conn_btree_apply(WT_SESSION_IMPL *session, const char *uri,
+__wt_conn_btree_apply(WT_SESSION_IMPL *session, bool skip_read, const char *uri,


Instead of having a special case arg here, maybe consider changing the __wt_checkpoint_get_handles function to skip readonly btrees? After all, that function already skips certain files, like history.

Good suggestion thanks! That will make the change much more simple. I'll submit a new change for review.

quchenhao · 2026-02-23T05:11:28Z

src/include/extern.h

  const char *config, const char *type, const char *check)
  WT_GCC_FUNC_DECL_ATTRIBUTE((warn_unused_result));
-extern int __wt_conn_btree_apply(WT_SESSION_IMPL *session, const char *uri,
+extern int __wt_conn_btree_apply(WT_SESSION_IMPL *session, bool skip_read, const char *uri,


sorry, I mean skip_readonly.

wiredtiger-prbot · 2026-02-23T05:33:54Z

Woohoo, the code changed in this PR is pretty well tested! 🎉

Metric (for added/changed code)	Coverage
Line coverage	100% (2/2)
Branch coverage	100% (4/4)

quchenhao

lgtm

src/checkpoint/checkpoint_txn.c

bvpvamsikrishna

lgtm

src/checkpoint/checkpoint_txn.c

etienneptl

LGTM once the last comment has been addressed.

whoisong requested review from ddanderson, etienneptl and quchenhao February 23, 2026 04:22

whoisong changed the title ~~Wt 15766 skip readonly btree for checkpoint~~ WT-15766 skip readonly btree for checkpoint Feb 23, 2026

quchenhao reviewed Feb 23, 2026

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whoisong requested a review from bvpvamsikrishna February 23, 2026 04:30

ddanderson reviewed Feb 23, 2026

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quchenhao changed the title ~~WT-15766 skip readonly btree for checkpoint~~ WT-15766 Skip readonly btree for checkpoint Feb 23, 2026

quchenhao reviewed Feb 23, 2026

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WT-15766 skip readonly btree in checkpoint

462ac69

whoisong force-pushed the wt-15766-skip-readonly-btree-for-checkpoint branch from 5fc199f to 462ac69 Compare February 23, 2026 21:52

whoisong requested review from ddanderson and quchenhao February 23, 2026 21:54

quchenhao approved these changes Feb 23, 2026

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etienneptl reviewed Feb 23, 2026

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src/checkpoint/checkpoint_txn.c Outdated Show resolved Hide resolved

whoisong marked this pull request as ready for review February 23, 2026 22:20

whoisong requested a review from a team as a code owner February 23, 2026 22:20

bvpvamsikrishna approved these changes Feb 23, 2026

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src/checkpoint/checkpoint_txn.c Outdated Show resolved Hide resolved

etienneptl approved these changes Feb 24, 2026

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Simplify comment

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whoisong added this pull request to the merge queue Feb 24, 2026

Merged via the queue into develop with commit def4af2 Feb 24, 2026
14 checks passed

whoisong deleted the wt-15766-skip-readonly-btree-for-checkpoint branch February 24, 2026 03:20

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