Re: [squid-users] Squid network read()'s only 2k long?

From: Declan White <declanw_at_is.bbc.co.uk>
Date: Mon, 1 Nov 2010 23:20:52 +0000

On Mon, Nov 01, 2010 at 10:55:12PM +0000, Declan White wrote:
> On Mon, Nov 01, 2010 at 09:36:53PM +0000, Amos Jeffries wrote:
> > On Mon, 1 Nov 2010 15:00:21 +0000, declanw_at_is.bbc.co.uk wrote:
> > > I went for a rummage in the code for the buffer size decisions, but got
> > > very very lost in the OO abstractions very quickly. Can anyone point me at
> > > anything I can tweak to fix this?
> >
> > It's a global macro defined by auto-probing your operating systems TCP
> > receiving buffer when building. Default is 16KB and max is 64KB. There may
> > also be auto-probing done at run time.
> >
> > It is tunable at run-time with
> > http://www.squid-cache.org/Doc/config/tcp_recv_bufsize/
>
> Oh thank God! Thanks :) (and annoyed with myself that I missed that)

Nuts.. actually, that didn't do anything :(

17314: write(16, " G E T / c f g m a n .".., 639) = 639
17314: ioctl(6, DP_POLL, 0x100459B90) = 1
17314: write(6, "\0\0\010\b\0\0\0\0\0\010".., 16) = 16
17314: ioctl(6, DP_POLL, 0x100459B90) = 1
17314: read(11, " H T T P / 1 . 1 2 0 0".., 2046) = 2046
17314: write(6, "\0\0\0\n\004\0\0", 8) = 8
17314: ioctl(6, DP_POLL, 0x100459B90) = 2
17314: write(10, " H T T P / 1 . 0 2 0 0".., 2180) = 2180
17314: read(11, " f o n t - s i z e : 3".., 2046) = 834
17314: ioctl(6, DP_POLL, 0x100459B90) = 2
17314: write(10, " f o n t - s i z e : 3".., 834) = 834
17314: read(11, " n o n e ;\n }\n\n # m".., 2046) = 1066
17314: ioctl(6, DP_POLL, 0x100459B90) = 1
17314: write(10, " n o n e ;\n }\n\n # m".., 1066) = 1066
17314: write(8, " [ 0 1 / N o v / 2 0 1 0".., 403) = 403

It's still reading from the remote server in 2046 byte lumps, which meant
three trips round the event loop where it might only have needed one.

I'm guessing that setting is for the kernel level TCP receive buffer, and
not the application read-from-that-buffer size.

I even doubled HTTP_REQBUF_SZ in defines.h for fun, and that did nothing
either. I can't find where the read() size might be decided in the code.

DeclanW
Received on Mon Nov 01 2010 - 23:20:57 MDT

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