go: x/build: frequent timeouts running js-wasm TryBots

I’ve noticed that the js-wasm TryBots on my recent CLs seem to start with one or more spurious failures before finally running successfully.

I suspect that that increases load on the TryBots generally, and may increase overall TryBot latency in some circumstances.

A log from a recent example is here (https://farmer.golang.org/temporarylogs?name=js-wasm&rev=9516a47489b92b64e9cf5633e3ab7e37def3353f&st=0xc00ab39b80):

  builder: js-wasm
      rev: 9516a47489b92b64e9cf5633e3ab7e37def3353f
 buildlet: (nil *buildlet.Client)
  started: 2019-10-26 01:37:51.137407213 +0000 UTC m=+287652.939853079
    ended: 2019-10-26 01:38:21.20458221 +0000 UTC m=+287683.007028020
  success: false

Events:
  2019-10-26T01:37:51Z ask_maintner_has_ancestor 
  2019-10-26T01:38:21Z finish_ask_maintner_has_ancestor after 30s; err=context deadline exceeded

Build log:
Error checking whether commit 9516a47489b92b64e9cf5633e3ab7e37def3353f includes ancestor 3dced519cbabc213df369d9112206986e62687fa: context deadline exceeded


Error: context deadline exceeded

CC @dmitshur @toothrot @bradfitz

About this issue

Original URL
State: closed
Created 5 years ago
Comments: 19 (17 by maintainers)

Commits related to this issue

dashboard: stop checking whether the branch/rev supports js/wasm for js/wasm It's supported it for ages. We no longer support or build branches that didn't have js/wasm support. See https://github.c... — committed to golang/build by bradfitz 5 years ago
dashboard: stop checking whether the branch/rev supports js/wasm for js/wasm It's supported it for ages. We no longer support or build branches that didn't have js/wasm support. See https://github.c... — committed to codebien/build by bradfitz 5 years ago
dashboard: disable reboot test on js-wasm builder The reboot test verifies that the modified version of Go can be used for bootstrapping purposes. The js-wasm builder is configured with GOHOSTOS=linu... — committed to golang/build by dmitshur 3 years ago

Most upvoted comments

Sounds good, closing since I haven’t seen reports of this in a long while, can reopen or file another issue if this comes up again.

From looking at the initial report, there’s also a chance that the same problem as in issue #55947 (fixed as of Oct 2022) may have contributed here too.

dmitshur on Jan 9, 2023

I’m also experiencing js-wasm slowdowns for my trybot runs. Here is an example:

Screenshot from 2020-10-30 13-18-40

Log (https://farmer.golang.org/temporarylogs?name=js-wasm&rev=ff065bd219cd7a9df01466e338b28f1891671da3&st=0xc0184e91e0):

  builder: js-wasm
      rev: ff065bd219cd7a9df01466e338b28f1891671da3
 buildlet: (nil *buildlet.Client)
  started: 2020-10-30 16:46:48.188839196 +0000 UTC m=+727935.299326955
   status: still running

Events:
  2020-10-30T16:46:48Z checking_for_snapshot 
  2020-10-30T16:46:48Z finish_checking_for_snapshot after 23.9ms
  2020-10-30T16:46:48Z get_buildlet 
 +2093.2s (now)

Build log:

(buildlet still starting; no live streaming. reload manually to see status)

Seems as though it is not getting past “get buildlet”.

[Edit: did finally make progress after 40 min wait.]

thanm on Oct 30, 2020

Yes, it is still happening. Last week I caught the js-wasm trybot taking 25 minutes when most were done in 15, and just now I caught it taking 34 minutes when everything else was done in 16. That one was https://go-review.googlesource.com/c/go/+/266357 and I gave up waiting and just submitted the CL.

Any advice about what to do when js-wasm looks like it is stuck/very slow and how to debug further would be greatly appreciated.

rsc on Oct 29, 2020