Michael Smith has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/22215 )

Change subject: IMPALA-13478: Sync tuple cache files to disk asynchronously
......................................................................


Patch Set 8:

(3 comments)

http://gerrit.cloudera.org:8080/#/c/22215/8//COMMIT_MSG
Commit Message:

http://gerrit.cloudera.org:8080/#/c/22215/8//COMMIT_MSG@24
PS8, Line 24: writing. UpdateWriteSize() can fail if it hits the limit on
What are the odds that this results in not writing any cache hits because rows 
are being produced too quickly and earlier writes were still in-progress, and 
that somehow this happens for most of the entries?

Trying to think through if this results in a situation where slow disk is 
unable to write any entry because several are running concurrently, slowing 
each other down and using up available write buffer, and all are evicted before 
they can complete. Maybe just most would be evicted?


http://gerrit.cloudera.org:8080/#/c/22215/8//COMMIT_MSG@44
PS8, Line 44:  - number of syncs calls that fail (due to IO errors)
nit: this line pluralizes sync, the next line doesn't. Seems inconsistent.


http://gerrit.cloudera.org:8080/#/c/22215/8/be/src/runtime/tuple-cache-mgr.cc
File be/src/runtime/tuple-cache-mgr.cc:

http://gerrit.cloudera.org:8080/#/c/22215/8/be/src/runtime/tuple-cache-mgr.cc@441
PS8, Line 441:       cache_->Erase(cache_->Key(handle->cache_handle));
A VLOG_FILE note might be nice here.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I646bb56300656d8b8ac613cb8fe2f85180b386d3
Gerrit-Change-Number: 22215
Gerrit-PatchSet: 8
Gerrit-Owner: Joe McDonnell <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Joe McDonnell <[email protected]>
Gerrit-Reviewer: Kurt Deschler <[email protected]>
Gerrit-Reviewer: Michael Smith <[email protected]>
Gerrit-Reviewer: Yida Wu <[email protected]>
Gerrit-Comment-Date: Fri, 02 May 2025 21:26:40 +0000
Gerrit-HasComments: Yes

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