[sldev] Linux 64 bit framerate stutter (0.5 - 2.0 second frame periodically [every 5 to 60 seconds])

[Robin Cornelius]

Bane Darrow wrote:
>     >
>     > I finally traced it down to llurlrequest.cpp:process_impl where it
>     calls
>     > mDetail->mCurlRequest->perform(). That eventually calls through to
>     > LLCurl::Multi::perform(), which calls curl_multi_perform(). From this
>     > point, it's hard to debug, as I'm not sure the best places to add new
>     > LLFastTimer() calls. It could either be getting stuck inside curl, or
>     > inside one of the callbacks in linden code. Finding it is hard because
>     > the stutters aren't long enough that I can break in and see where
>     the PC

> 
>     i'm on my own anti-stutter mission which may or may not be the same as
>     yours, as my stutters are 10 seconds i may stand a chance of a gdb
>     break.
> 
> 
> Please let me know what you find out, and I'll do the same.
>  


I agree its a curl function and i got a back trace into it too :-

Its in the comments on VWR-5601. I opened a JIRA the other day as
although there are many JIRA's relating to stutter, this one has a
specific repro and cause and could indeed be the root cause of (some)
other reported stutters in the viewer.

BTW using a local cacheing DNS improves this problem by a factor of 10,
i now get 1 second stutters that i hardly notice instead of 10 second.

Not sure if its useful but i can turn off my local DNS and enable debug
symbols on libcurl and other libraries if you want to see the full code
path.

Robin