Performance: PGO applicability

[zamazan4ik]

Description
I suggest adding PGO (+ BOLT) support to the project. According to my local tests, I have reached with sky-bench -q1000000 -r20 the following results (local runs on Apple Macbook M1 Pro):
Without PGO (default release build):

===========RESULTS===========
SET    140810.697866/sec
UPDATE 146618.948096/sec
GET    137469.544488/sec
=============================

With PGO:

===========RESULTS===========
SET    153383.657977/sec
UPDATE 156045.351506/sec
GET    159065.787814/sec
=============================

Results are a little bit unstable but the PGO version is always more performant than non-PGO. BOLT (LLVM BOLT) also could help here but I haven't tested it yet.

Suggested solutions

• Optimize provided to the users' binaries with PGO and BOLT (if any)
• Write a note in the project about optimizing Skytable with PGO to gain even more performance

More PGO-related benchmark results (including many databases like Redis, PostgreSQL, ClickHouse) are available here - https://github.com/zamazan4ik/awesome-pgo .

[ohsayan]

Thanks for the note. We can surely incorporate this into the build pipeline (although it'll need a bunch of changes).

[zamazan4ik]

@ohsayan Do you have updates regarding PGO in Skytable?

Since the integration into the build pipelines could take some time, I suggest at least writing a note somewhere in the documentation regarding PGO and Skytable. So the users/maintainers will be aware of this way to achieve better performance with Skytable and will be able to recompile Skytable according to their workloads. Here are some examples:

• ClickHouse: https://clickhouse.com/docs/en/operations/optimizing-performance/profile-guided-optimization
• Databend: https://databend.rs/doc/contributing/pgo
• Vector: https://vector.dev/docs/administration/tuning/pgo/
• Nebula: https://docs.nebula-graph.io/3.5.0/8.service-tuning/enable_autofdo_for_nebulagraph/
• GCC: Official docs, section "Building with profile feedback" (even AutoFDO build is supported)
• Clang:
  • https://llvm.org/docs/HowToBuildWithPGO.html
  • https://llvm.org/docs/AdvancedBuilds.html