write_buf_size > buffer_size_reproxy_url

[Eric Lambrecht]

Have anybody ever seen a problem where ClientProxy is reproxying a file 
and the write_buf_size is larger than what should be allowed by 
buffer_size_reproxy_url?

This seems to be a consistent issue with us, and we're trying to figure 
out what is going on. Here's an example set of lines from the perlbal 
management interface:

>    81   184s Perlbal::ClientProxy(RW): open to 85.96.xxx.xxx:2020: localport=8082; reqs=1; xfer_res; http://free.guba.com/free!1130968494!8e3e6c9810f74e6aa71e15dd55eff018/r/2000585938/one.mpg; backend=brittany.guba.com:7500; responded
>    82   102s Perlbal::ClientProxy(RW): open to 24.166.xx.xxx:3571: localport=8082; reqs=1; xfer_res; http://free.guba.com/free!1130968569!560eb0f82374998d93b8a73bcc6d3d77/r/2000586487/two.mpeg; backend=noah.guba.com:7500; responded
>    83     3s Perlbal::ClientProxy(R): open to 207.250.xxx.xx:5067: localport=8082; reqs=1; wait_backend; http://free.guba.com/free!1130968670!f65bc752f3162a48c0e6d53b46acabb4/r/2000585994/three.wmv
>    84   195s Perlbal::ClientProxy(RW): open to 84.176.xxx.xx:2742: localport=8082; reqs=1; xfer_res; http://free.guba.com/free!1130968554!38bb4bfb4de5bf5ea2c090f9e7790fe4/r/2000585907/four.wmv; write_buf_size=10677231; responded
>    85    55s Perlbal::ClientProxy(RW): open to 24.203.xxx.xx:2008: localport=8082; reqs=1; xfer_res; http://free.guba.com/free!1130968709!0ea90700b54d170ea03c2cff66706f14/r/2000585696/five.mpg; write_buf_size=92577; responded

See the insane write buffer size in line 84?

We think the $client->{backend} variable is somehow disappearing, the 
$client->too_far_behind_backend() function is always returning 0, and a 
backend is still writing stuff to the client (so the file ultimately 
gets delivered).

When you're serving a bunch of files, these huge buffer sizes can really 
start to eat up the server.

Any ideas?

Eric...