deno 0.25.0 or later sometimes hangs up on single core processor.

[horihiro]

I tried to execute deno on Azure App Service on Linux also (PaaS service based on Linux).

I confirmed that deno 0.24.0 or before worked without any problem.
But when using 0.25.0 or later, the execution is hang up even if the following simple code.

# deno eval "import { serve } from 'https://deno.land/std/http/server.ts';"
Compile https://deno.land/std/http/server.ts
Download https://deno.land/std/io/bufio.ts
Download https://deno.land/std/textproto/mod.ts
Download https://deno.land/std/http/http_status.ts
Download https://deno.land/std/testing/asserts.ts
Download https://deno.land/std/util/async.ts
(hang up)

App Service on Linux is based on Docker, so I tried deno 0.25.0 on the container image (ex. appsvc/php:5.6-apache_20191031.7, which is used on the App Service on Linux) on local Docker, and I confirmed it worked.

I think this is compatibility issue between App Service on Linux and deno 0.25.0 or later.

Could you please let me know any other check points in order to make deno work if you know?

I would appreciate your help.

Best Regards,

[kitsonk]

Can you add -L debug to the command line please?

[horihiro]

Hi @kitsonk

I attached log file generated by deno eval "import { serve } from 'https://deno.land/std/http/server.ts';" -L debug > debug.log
debug.log

Could you please look into it?

Regards,

[kitsonk]

How is this different than #3464?

[horihiro]

This issue is about Linux platform.

3464 is about Windows platform.

[horihiro]

any comments?

[horihiro]

I found that this issue occurs on combination of single core processor and v0.25.0 or later only.
This is similar to #2124 .

[horihiro]

I confirmed same behavior on local docker container (appsvc/php:5.6-apache_20191031.7) launched with cpu count restricted by --cpuset-cpus=0 option.

[hayd]

potentially will be fixed by tokio 0.2 update (maybe it's due to one of the few block_ons).

once fixed, should add a test with taskset to restrict to one cpu.

[kevinkassimo]

cc @bartlomieju
I wonder if it has something to do with #3381 ...

[bartlomieju]

cc @bartlomieju
I wonder if it has something to do with #3381 ...

Yeah, that might be the problem, I'd wait a few more days, we're waiting only for reqwest at this point to move to Tokio 0.2 (already updated just waiting on release). It should be easier to reason about it then.

[bartlomieju]

@horihiro @kevinkassimo just tried it with tokio 0.2 - it seems to work even with single core available. Gonna keep this issue open until we cut a new release containing tokio upgrade.

EDIT: Just release in v0.28.0 (#3574), @horihiro could you verify that it's working for you?

[horihiro]

Thanks @bartlomieju !

v0.28.0 is working very well!

I close this issue.