utils: remove unnecessary fsync in durable_rename()

[erikgrinaker]

Problem

WAL segment fsyncs significantly affect WAL ingestion throughput. durable_rename() is used when initializing every 16 MB segment, and issues 3 fsyncs of which 1 was unnecessary.

Touches #9664.

Summary of changes

Remove an fsync in durable_rename which is unnecessary with Linux and ext4 (which we currently use). This improves WAL ingestion throughput by up to 23% with large appends on my MacBook.

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[erikgrinaker]

Benchmarks on my MacBook, ingesting 1 GB of WAL with varying AppendRequest sizes via WAL acceptor with fsync enabled.

wal_acceptor_throughput/fsync=true/commit=false/size=1024
                        time:   [13.191 s 13.238 s 13.289 s]
                        thrpt:  [77.054 MiB/s 77.352 MiB/s 77.627 MiB/s]
                 change:
                        time:   [-3.5965% -2.9042% -2.3172%] (p = 0.00 < 0.05)
                        thrpt:  [+2.3721% +2.9911% +3.7306%]
wal_acceptor_throughput/fsync=true/commit=false/size=8192
                        time:   [2.8743 s 2.8978 s 2.9210 s]
                        thrpt:  [350.57 MiB/s 353.38 MiB/s 356.26 MiB/s]
                 change:
                        time:   [-10.334% -9.1313% -7.9787%] (p = 0.00 < 0.05)
                        thrpt:  [+8.6704% +10.049% +11.526%]
wal_acceptor_throughput/fsync=true/commit=false/size=131072
                        time:   [1.4600 s 1.4773 s 1.4943 s]
                        thrpt:  [685.29 MiB/s 693.14 MiB/s 701.36 MiB/s]
                 change:
                        time:   [-20.188% -18.542% -16.896%] (p = 0.00 < 0.05)
                        thrpt:  [+20.331% +22.762% +25.294%]
wal_acceptor_throughput/fsync=true/commit=false/size=1048576
                        time:   [1.6651 s 1.6824 s 1.7033 s]
                        thrpt:  [601.18 MiB/s 608.66 MiB/s 614.97 MiB/s]
                 change:
                        time:   [-19.657% -17.659% -15.607%] (p = 0.00 < 0.05)
                        thrpt:  [+18.493% +21.447% +24.467%]

[github-actions]

5382 tests run: 5162 passed, 0 failed, 220 skipped (full report)

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Code coverage* (full report)

• functions: 31.8% (7882 of 24824 functions)
• lines: 49.4% (62416 of 126224 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
bf2bb60 at 2024-11-12T15:11:08.124Z :recycle:}