You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@httpd.apache.org by John Heidemann <jo...@ISI.EDU> on 1996/10/29 03:06:07 UTC
potential Apache performance problem: size of the TCP send buffer
Apache-1.1.1 doesn't appear to set the size of the TCP send buffer.
On many systems the default send-buffer size is too small to support
full-rate transfer over high bandwidth-delay-product networks (such as
cross-US Internet traffic). For example, a 100ms round-trip time
(typical cross-US latency) and a 4kB default buffer size (common to
many OSes such as SunOS) limit transfer rate to 40kB/s.
Much better cross-US transfer rates are possible between
well-connected hosts if the send buffer size is increased. A patch at
<http://www.isi.edu/~johnh/SOFTWARE/APACHE/apache_1.1.1_isi_set_sndbuf.patch>
implements the SendBufferSize directive to allow Apache to have a
configurable buffer size.
A complete description of this directive is in the file
send_buffer_size.html which accompanies the patch. For a pointer to
other patches, see <http://www.isi.edu/~johnh/SOFTWARE/APACHE>. For
descriptions of the problems motivating these patches, see
<http://www.isi.edu/lsam/publications/phttp_tcp_interactions/>. [For
those of you who have seen this web page before, there are some new
figures in ``The Performance Problems'' section and the buffer-size
problem is described under ``Other Problems'' there.]
-John Heidemann
USC/ISI
Re: potential Apache performance problem: size of the TCP send buffer
Posted by Brian Behlendorf <br...@organic.com>.
This patch looks good to me - a patch against the current cvs tree is appended.
Any other +1's?
Brian
On Mon, 28 Oct 1996, John Heidemann wrote:
> Apache-1.1.1 doesn't appear to set the size of the TCP send buffer.
> On many systems the default send-buffer size is too small to support
> full-rate transfer over high bandwidth-delay-product networks (such as
> cross-US Internet traffic). For example, a 100ms round-trip time
> (typical cross-US latency) and a 4kB default buffer size (common to
> many OSes such as SunOS) limit transfer rate to 40kB/s.
>
> Much better cross-US transfer rates are possible between
> well-connected hosts if the send buffer size is increased. A patch at
> <http://www.isi.edu/~johnh/SOFTWARE/APACHE/apache_1.1.1_isi_set_sndbuf.patch>
> implements the SendBufferSize directive to allow Apache to have a
> configurable buffer size.
>
> A complete description of this directive is in the file
> send_buffer_size.html which accompanies the patch. For a pointer to
> other patches, see <http://www.isi.edu/~johnh/SOFTWARE/APACHE>. For
> descriptions of the problems motivating these patches, see
> <http://www.isi.edu/lsam/publications/phttp_tcp_interactions/>. [For
> those of you who have seen this web page before, there are some new
> figures in ``The Performance Problems'' section and the buffer-size
> problem is described under ``Other Problems'' there.]
>
> -John Heidemann
> USC/ISI
>
>
>
>
>
--=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--
brian@organic.com www.apache.org hyperreal.com http://www.organic.com/JOBS