safekeeper: use jemalloc

[erikgrinaker]

Problem

To add Safekeeper heap profiling in #9778, we need to switch to an allocator that supports it. Pageserver and proxy already use jemalloc.

Touches #9534.

Summary of changes

Use jemalloc in Safekeeper.

[github-actions]

6952 tests run: 6644 passed, 0 failed, 308 skipped (full report)

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Flaky tests (2)

Postgres 17

• test_pg_regress[None]: release-x86-64

Postgres 15

• test_pull_timeline[True]: release-arm64

Code coverage* (full report)

• functions: 30.2% (8175 of 27038 functions)
• lines: 47.6% (64710 of 135838 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
33b141d at 2024-11-29T13:27:39.853Z :recycle:}

[erikgrinaker]

TFTR! I should run a few benchmarks before merging this, but don't expect any issues.

[erikgrinaker]

I added a bytes_reserve benchmark which emulates the allocations made when parsing inbound WAL messages. This shows a substantial improvement of up to 100% for larger allocations on Linux.

On macOS (not included here), jemalloc had roughly equivalent performance to the default allocator. This makes sense since they're both region-based allocators.

bytes_reserve/size=1    time:   [13.340 ns 13.402 ns 13.467 ns]
                        thrpt:  [70.817 MiB/s 71.160 MiB/s 71.491 MiB/s]
                 change:
                        time:   [-2.9146% -2.5058% -2.1043%] (p = 0.00 < 0.05)
                        thrpt:  [+2.1495% +2.5702% +3.0021%]

bytes_reserve/size=64   time:   [16.534 ns 16.572 ns 16.616 ns]
                        thrpt:  [3.5872 GiB/s 3.5967 GiB/s 3.6049 GiB/s]
                 change:
                        time:   [-8.4769% -8.3165% -8.1326%] (p = 0.00 < 0.05)
                        thrpt:  [+8.8525% +9.0708% +9.2620%]

bytes_reserve/size=1024 time:   [26.292 ns 26.673 ns 27.053 ns]
                        thrpt:  [35.252 GiB/s 35.755 GiB/s 36.273 GiB/s]
                 change:
                        time:   [-3.0939% -1.8861% -0.7759%] (p = 0.00 < 0.05)
                        thrpt:  [+0.7820% +1.9223% +3.1927%]

bytes_reserve/size=8192 time:   [69.892 ns 69.907 ns 69.923 ns]
                        thrpt:  [109.11 GiB/s 109.14 GiB/s 109.16 GiB/s]
                 change:
                        time:   [-49.603% -49.583% -49.560%] (p = 0.00 < 0.05)
                        thrpt:  [+98.256% +98.344% +98.426%]

bytes_reserve/size=131072
                        time:   [1.5824 µs 1.6067 µs 1.6337 µs]
                        thrpt:  [74.720 GiB/s 75.977 GiB/s 77.143 GiB/s]
                 change:
                        time:   [-18.309% -17.334% -16.544%] (p = 0.00 < 0.05)
                        thrpt:  [+19.823% +20.969% +22.412%]