Nginx stops sending file after ~1.5mb ?

[Igor Sysoev]

On Wed, Jan 21, 2009 at 01:52:53AM +0200, Yo'av Moshe wrote:

> Igor, here's the new strace.
> http://pastebin.com/m5129c54b
> 
> Does the fact it works in low download rates still makes you think it's a
> kernel issue?

Yes, this is seems like a kernel issue. Kernel excatly said (with EAGAIN)
that there is no place to output data, but never returned a new notification
via epoll_wait() about free space:

21420 01:39:43 <... epoll_wait resumed> {{EPOLLOUT, {u32=153137960, u64=13811628390360331048}}}, 512, 60000) = 1
21420 01:39:43 gettimeofday({1232494783, 413764}, NULL) = 0
21420 01:39:43 sendfile64(20, 21, [1645625], 304605) = 40320
21420 01:39:43 sendfile64(20, 21, [1685945], 264285) = -1 EAGAIN (Resource temporarily unavailable)
21420 01:39:43 epoll_wait(11,  <unfinished ...>

This is probably some race condition inside kernel, that does not appear on
low speed download.

> Thank you, really!
> And thanks, Kiril and Jeff, for confirming that!
> 
> Yo'av.
> 
> 
> On Tue, Jan 20, 2009 at 9:39 PM, Kiril Angov <kupokomapa at gmail.com> wrote:
> 
> > wget http://www.noal.org.il/static/temp/barvazi2.pdf
> > --2009-01-20 21:36:00--  http://www.noal.org.il/static/temp/barvazi2.pdf
> > Resolving www.noal.org.il... 195.28.180.147
> > Connecting to www.noal.org.il|195.28.180.147|:80... connected.
> > HTTP request sent, awaiting response... 200 OK
> > Length: 1950230 (1.9M) [application/pdf]
> > Saving to: `barvazi2.pdf'
> >
> > 81% [=====================================>         ] 1,596,665
> > --.-K/s  eta 5s
> >
> >
> > wget -c http://www.noal.org.il/static/temp/barvazi2.pdf
> > --2009-01-20 21:38:28--
> > http://www.noal.org.il/static/temp/barvazi2.pdf
> > Resolving www.noal.org.il... 195.28.180.147
> > Connecting to www.noal.org.il|195.28.180.147|:80... connected.
> > HTTP request sent, awaiting response... 206 Partial Content
> > Length: 1950230 (1.9M), 305960 (299K) remaining [application/pdf]
> > Saving to: `barvazi2.pdf'
> >
> > 100%[+++++++++++++++++++++++++++++++++++++++=======>] 1,950,230
> > 295K/s   in 1.0s
> >
> > 2009-01-20 21:38:30 (295 KB/s) - `barvazi2.pdf' saved [1950230/1950230]
> >
> >
> > On Tue, Jan 20, 2009 at 9:31 PM, jeff emminger <jemminger at gmail.com>
> > wrote:
> > >> Could anyone confirm that this works:
> > >> wget --limit-rate=3500 http://www.noal.org.il/static/temp/barvazi2.pdf
> > >> while this doesn't:
> > >> wget http://www.noal.org.il/static/temp/barvazi2.pdf
> > >>
> > >
> > > Confirmed
> > >
> > >
> >
> >
> 
> 
> -- 
> Yo'av Moshe

-- 
Igor Sysoev
http://sysoev.ru/en/