On Tue, May 7, 2013 at 3:00 PM, Daniel Stenberg <daniel_at_haxx.se> wrote:

> On Tue, 7 May 2013, Alex Loukissas wrote:
>
> I'm using the curl_multi interface to make parallel GET requests on a set
>> of URLs. I've noticed that at times the call to curl_multi_wait may block
>> indefinitely, despite the fact that I'm passing in a value of 1000 (msec)
>> to the timeout_ms parameter. Some snippets from my debugger:
>>
>> 00000000`0933e5d0 00000001`3f5233d4 ws2_32!select+0x75a
>> 00000000`0933e6d0 00000001`3f4fcb28 mag_client!Curl_poll+0x234
>> [c:\curl-7.28.1\lib\select.c @ 474]
>> 00000000`0933eda0 00000001`3f31f653 mag_client!curl_multi_wait+**0x1d8
>> [c:\curl-7.28.1\lib\multi.c @ 1029]
>>
>
> Ouch. That seems really strange!
>

Yes rather strange behavior, although it's not very frequent. Do you
perhaps have a hunch on anything I might have missed in the way I'm using
curl_multi interface?

>
> I've stumbled across a perhaps relevant blog
>> post<http://daniel.haxx.se/**blog/2012/10/10/wsapoll-is-**broken/<http://daniel.haxx.se/blog/2012/10/10/wsapoll-is-broken/>
>> >,
>> which could be related.
>>
>
> By the way, this was seen on Win7 and my app is using a libcurl 7.28.1,
>> statically linked.
>>
>
> We stopped using WSAPoll() already in 7.28.0 so _that_ is not the reason
> here, and as you see in your stack trace libcurl called select() ...

Indeed..

>
>
> --
>
> / daniel.haxx.se
> ------------------------------**------------------------------**-------
> List admin: http://cool.haxx.se/list/**listinfo/curl-library<http://cool.haxx.se/list/listinfo/curl-library>
> Etiquette: http://curl.haxx.se/mail/**etiquette.html<http://curl.haxx.se/mail/etiquette.html>
>

-- 
Alex Loukissas
Member of Technical Staff - Maginatics, Inc.
www.maginatics.com

-------------------------------------------------------------------
List admin: http://cool.haxx.se/list/listinfo/curl-library
Etiquette: http://curl.haxx.se/mail/etiquette.html
Received on 2013-05-08