Michael Pratt

Currently our AWS darwin-amd64 builder guests take ~4 minutes to boot. This is much slower than guests on MacStadium (I'm told those were closer to 10s). 4 minute boot time...

I added tracing to QEMU, and these are the VM exit reason counts during boot: ``` 25338097 hvf_vcpu_exit: exit reason 48 (EPT violation) 1465860 hvf_vcpu_exit: exit reason 7 (Interrupt window)...

For reference, buildlet wait times (`get_buildlet`, seconds): Before AWS switch (2022-10-15 through 2022-11-29): |Builder|p10|p50|p90|p99| |---|---|---|---|---| |darwin\-amd64\-10\_14|0\.035087506|57\.426122709|5409\.986448872|27029\.738440022| |darwin\-amd64\-10\_15|0\.035315248|51\.394408839|6330\.141066737|33205\.196756675| |darwin\-amd64\-11\_0|0\.03502191|17\.052950941|1265\.639361792|18768\.733989156| |darwin\-amd64\-12\_0|0\.036329005|113\.757215006|27884\.264082743|60902\.939780661| |darwin\-amd64\-nocgo|0\.036361308|152\.538390709|33514\.425559542|60922\.292660581| After AWS switch (2022-11-30 through 2023-01-12): |Builder|p10|p50|p90|p99| |---|---|---|---|---| |darwin\-amd64\-10\_14|0\.030347397|129\.170084819|16868\.565147715|51138\.059929517| |darwin\-amd64\-10\_15|0\.032052233|165\.560549426|21411\.865571222|53629\.770950752|...

Now it is better! https://perf.golang.org/dashboard/?benchmark=AppendMsgReplicateDecision-8&days=200&end=2022-12-21T15%3A45

There are feature requests on `debug/gosym`, such as #58474, which would be folded into the new x/debug packages. Though the title is about the `gocore` package, we envision having an...

The coordinator changes are in, so linux-amd64-perf builders are now running for x/tools on the release branches. Builds are failing because cmd/bench needs to add support for the tools repo.

Sounds good, go for it.

I took a look at what is going on: * Thread 1: throwing * Holding paniclk * Waiting for printlock * Thread 2: sysmon * Holding ?? * Waiting for...

Another option may be to have `throw` take `printlock` prior to `paniclk`. I'm not sure if there is a concrete reason we don't do that currently. This would have the...

I have a few minor questions: 1. What is the output format of these profiles? Still pprof, I assume (rather than perf.data)? In that case, are there special considerations we...