jamadden
commented
4 years ago Benchmarks look good. Adding non-conflicting objects is not impacted. Using 60 greenlets to update 1,000 conflicting objects looks very nice:
| 60 greenlets/1,000 conlficts | Time (ms) | CPU Usage |
|---|---|---|
| This branch | 284 | 75% |
| Master (default commit-timeout) | Failed | Failed |
| Master (60s commit-timeout) | 719 | 50% |
The default settings for master couldn't finish this test: many greenlets died by timing out to lock rows. With an extended timeout, master could complete the test, taking 719ms and never using more than 50% CPU. With these changes, however, we cut that time down to just 284ms and make better use of the CPU.
Prefetch states needed for conflict resolution in a single query. Ensure that we use the cache for these states. This benefits all drivers.
Be explicit about when to start elevated priority mode.
Those two items let us implement no-switch mode fully for queries as well, for both the load and store connections.
Also, avoid potentially blocking on the cache locks during this time.
Fixes #339.
Awaiting some benchmarking...