Repository: go
Issue: x/tools/cmd/fiximports: frequent TestDryRun and TestFixImports timeouts on plan9-arm since 2021-11-12
Labels: OS-Plan9,NeedsInvestigation,Tools,arch-arm

```
#!watchflakes
post <- builder ~ `^plan9` && pkg == "golang.org/x/tools/cmd/fiximports" && (test == "TestDryRun" || test == "TestFixImports")
```

`greplogs --dashboard -md -l -e 'panic: test timed out.*\n(?:.*\n)*golang\.org/x/tools/cmd/fiximports\.TestDryRun' --since=2021-01-01`

<details>

[2022-01-21T16:59:19-9f83dd3-9eba5ff/plan9-arm](https://build.golang.org/log/129df2c0d74b0dd0833d71bd0e3d656ba7a435b8)
[2022-01-19T14:58:28-a8c7459-2a061fd/plan9-arm](https://build.golang.org/log/ac9c69ee7cd345fd1ccbd901780f9e2f1b591103)
[2022-01-18T14:56:19-f29bdf1-5b3ebc8/plan9-arm](https://build.golang.org/log/4cf8f48b8bb91bd6cfcefc8b28f1735d8b069a78)
[2022-01-14T21:54:39-f29bdf1-3b5eec9/plan9-arm](https://build.golang.org/log/c5ab0370aedb349d72168a9f4d613893ebbf673e)
[2022-01-13T18:06:33-68b574a-4fa6e33/plan9-arm](https://build.golang.org/log/3e2fcaa7fdbb39d232ccf3e51a6556ab21e8b6ef)
[2022-01-13T17:30:17-68b574a-2423912/plan9-arm](https://build.golang.org/log/07704455c01088a9069a3d0e27d9c58c9b30f61c)
[2022-01-11T17:13:50-d7a4bb4-1abe9c1/plan9-arm](https://build.golang.org/log/f7df00e0583bdce0a10ad0087c64810feb6f7193)
[2022-01-11T14:03:54-d7a4bb4-90a8482/plan9-arm](https://build.golang.org/log/e2d5558e3398a9f8037f3e41120c78e6f5cf7bcf)
[2022-01-10T19:19:50-f234b3d-933f668/plan9-arm](https://build.golang.org/log/96d0ac32032f36acdb7dde2b79852413b200c571)
[2022-01-04T22:05:15-15409b5-e39ab9b/plan9-arm](https://build.golang.org/log/36ca257942c3278398551102099bb50ec9bdb138)
[2021-12-28T19:10:34-2c49d4f-b357b05/plan9-arm](https://build.golang.org/log/2be8a7689e0d17d0b3ffb065172874f3cd1b1544)
[2021-12-16T22:41:31-8d38310-1387b5e/plan9-arm](https://build.golang.org/log/eaa75843f1ceace933957a493c19d6ada11f7f59)
[2021-12-16T21:08:09-8d38310-ae695cd/plan9-arm](https://build.golang.org/log/38c62e8948206c179d33f53aa1a08e7166f600f0)
[2021-12-10T19:26:50-27fc764-766f89b/plan9-arm](https://build.golang.org/log/ba0158f9b16dda073aa30308d5ac256c18e759da)
[2021-12-09T15:47:16-27fc764-61ba0bc/plan9-arm](https://build.golang.org/log/62c9e8c468dd95ac6ed125b3cf64ea5d1b142447)
[2021-12-08T23:00:01-3fca6a0-f5ddd94/plan9-arm](https://build.golang.org/log/3eaf6ce0e9339fd4ad700553387b42777d56f4ea)
[2021-12-07T00:03:34-feb39d0-79b425e/plan9-arm](https://build.golang.org/log/546b671e04f0a02bffbfb8f395d91056a1e2b548)
[2021-12-06T17:34:53-feb39d0-2cb9042/plan9-arm](https://build.golang.org/log/ca7e1843571707774a81b41f952ea62e35b0b8d4)
[2021-12-06T16:11:25-feb39d0-f8a8a73/plan9-arm](https://build.golang.org/log/c18a71ee9af690efa151b5beefc029752c8b4591)
[2021-12-04T11:59:35-c882a49-1876b38/plan9-arm](https://build.golang.org/log/77775513c76ce508a6a91c3c81db85e7abecf248)
[2021-12-03T16:24:32-e212aff-29483b3/plan9-arm](https://build.golang.org/log/7a7a20c4a3e58e336e7db2bfbbba2c5ee9f5cb9d)
[2021-12-03T14:28:11-e212aff-a174638/plan9-arm](https://build.golang.org/log/52e69c0a7338250558b8f3d0711a944971d782da)
[2021-12-02T23:34:26-e212aff-5f65520/plan9-arm](https://build.golang.org/log/5b6c7b2aeb80c0029475a6890e7e33eab8115a1f)
[2021-12-01T19:09:57-d99d6fa-0103fd2/plan9-arm](https://build.golang.org/log/7a1abcacbdc80d6c195bb92e4d4ca3e727e8d00d)
[2021-12-01T18:47:44-3c63f30-08ecdf7/plan9-arm](https://build.golang.org/log/f0318653ea1dad5d19ad41654e3b0665f40bf1e4)
[2021-12-01T15:58:46-615f9a6-029dfbc/plan9-arm](https://build.golang.org/log/4be0f4ea8cc45aafd9fc8aaf732e19ef36f21033)
[2021-12-01T15:05:46-615f9a6-0e1d553/plan9-arm](https://build.golang.org/log/a8627d0dcb57da88035fbd276e9ebaac3f0a384a)
[2021-11-30T18:49:39-2c9b078-5f63f16/plan9-arm](https://build.golang.org/log/fb4d6a197f70a64225ce39e4740cbd556767b6db)
[2021-11-30T18:09:02-2c9b078-931d80e/plan9-arm](https://build.golang.org/log/17d316867fb3a4e4e966a55542bb9abe257bb260)
[2021-11-29T22:57:42-6e52f51-3ca57c7/plan9-arm](https://build.golang.org/log/ed0aa5dc1bb154c7adf7c20d777b32efa87f070f)
[2021-11-29T20:12:13-6e52f51-f598e29/plan9-arm](https://build.golang.org/log/6bbcbb221233d6d4fe28731413c001a37f452133)
[2021-11-29T16:08:23-a618923-a59ab29/plan9-arm](https://build.golang.org/log/6aa475096c7e2bf6d2391d68b22f8be6fb9f0dcb)
[2021-11-22T23:51:43-c2c92fd-83bfed9/plan9-arm](https://build.golang.org/log/4f53c909c3efc97bf93ba0045bc70cf98d6f3137)
[2021-11-22T21:22:40-c2c92fd-f13fcd9/plan9-arm](https://build.golang.org/log/9c7f87a17017a8ec6195cd52f9b261eb54c88a7a)
[2021-11-22T16:53:57-d0c7211-cd0bf38/plan9-arm](https://build.golang.org/log/992108311b16a04c980088bc28868af3bd4070db)
[2021-11-19T22:35:28-d0c7211-b31dda8/plan9-arm](https://build.golang.org/log/da0cf4f3c8c7128c79590049ce07232569ff2b08)
[2021-11-18T16:18:50-43b469a-feb330d/plan9-arm](https://build.golang.org/log/5d795e28dfb28ff033b906ad7682ddebc8843e80)
[2021-11-17T21:26:25-43b469a-0440fb8/plan9-arm](https://build.golang.org/log/52a8acaf2bf6a5e15e6071493496768de0b7385f)
[2021-11-17T19:51:32-43b469a-9a33945/plan9-arm](https://build.golang.org/log/2afd3caf532ee65f49dee17b352c4955bd5c002d)
[2021-11-17T19:16:04-43b469a-0981724/plan9-arm](https://build.golang.org/log/831c0b493289a5dba746de8559d87ee8f51d462f)
[2021-11-17T17:03:06-7d6c71f-4083a6f/plan9-arm](https://build.golang.org/log/e738c534b4a9b27b122fd01d98832ff8fc9aa41a)
[2021-11-16T14:26:19-1a3081d-bddb79f/plan9-arm](https://build.golang.org/log/69f9deefa97a5f15076e6fbec3fccacf487de08e)
[2021-11-15T15:42:24-49ce184-ce4a275/plan9-arm](https://build.golang.org/log/0bc30bf4a490f6e78af55aac7fcc01459c069ca3)
[2021-11-14T17:38:42-49ce184-5337e53/plan9-arm](https://build.golang.org/log/b42ccd116a2e9695f7a0894982e8ff25995db5c3)
[2021-11-12T20:20:57-fda06c1-76fbd61/plan9-arm](https://build.golang.org/log/48dc3583f89b99379dc030495fcecba6792f4b2e)

</details>

I assume that this has something to do with filesystem performance, but the difference is several orders of magnitude. This test runs in about 500ms on my Linux workstation, and it's timing out after 10 minutes on `plan9-arm`. 😅

(CC @millerresearch)