[squid-users] Corruption of downloads

Greetings,

I've recently been experiencing the unexplained corruption of some objects
requested through our squids. We are using version 2.4.STABLE7 on
solaris 8, compiled with the Sun WorkShop compiler (5.0 98/12/15 C 5.0).
Details of configure options below.

I'd be very interested to know if anyone else on the list has
experienced any problems or corruptions similar to these.

The corruptions take the form of another, unrelated response header
and body seemingly superimposed upon the body of the requested
object. A typical example is shown at the end of this email.
Although the contents are corrupted, the length of the downloaded
file is always correct. The corruptions can seemingly occur anywhere
within the file.

These problems have only been experienced with larger files, some tens of Mb
in size. However, the rate of these events is low (of the order of a
couple of corruptions per Gb of data returned to the client), so it is
possible that smaller files can experience similar problems.

After playing around with a number of test files, I suspect that the
objects are downloaded and stored in the cache in an uncorrupted state.
The problem appears to occur only (or at least more frequently)
as the file is sent from squid to the client.

These squid caches are quite busy. I have been unable to reproduce the
problem on a "quiet" cache.

This seems as if it might be a memory allocation problem, and is
probably going to be OS-specific. I am currently working on a binary
incorporating dlmalloc to see if this affects the behaviour.

I'd be interested to hear any other reports of similar strangeness.
Thanks!

Regards,
        Roy
           
--
Dr Roy Duncan, Software Infrastructure Group | Insert
Information Technology Services (Prentice) | terse
The University of Queensland, 4072, Australia | witticism
Email: ccroy@uq.edu.au Phone: +61-7-33654357 | here... . .

A typical corruption. This file consists of 546084 lines of "Q"s,
and is 44232804 bytes long. This corruption starts at byte 16936639,
appearing to be a small GIF image. I have translated some of the
nastier characters to "X".

QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQ^C^X^X^Xm^C^X^X^X^PXXGXXXHXB^CXIXX3a9jfXX^E^X^X^X^X=X^^G=X^^GXXXX8XXJ^X^X^X^X^X^A^DX^D^X^X^X0http://www.unicu.org.au/images/indexmenu01b.gif^X^HHTTP/1.1 200 OK^M
Server: Microsoft-IIS/4.0^M
Connection: keep-alive^M
Date: Mon, 08 Jul 2002 23:22:13 GMT^M
Content-Type: image/gif^M
Accept-Ranges: bytes^M
Last-Modified: Fri, 07 Apr 2000 06:16:42 GMT^M
ETag: "407e70d758a0bf1:cb06"^M
Set-Cookie: EGSOFTXID=130.102.5.60-1273619538.29856155; expires=Fri, 31-Dec-2010 00:00:00 GMT; path=/^M
Content-Length: 1007^M
^M
GIF89aX^X^V^XX^X^X^X^X^XXXXTKZIHnXXX;EXE2CXU/XXM^XXWX9^X9IXWCRXXQ^XXeqXXXXJXXXXXXXXXXX1lXXXXXXXXXXXXXXXXXXGXXlXX^XXX^XXXX^XXXV^XXXM^XXXC^XXw^XXj^XXMX^AXX^^XXX^XwU^XXXX^XXXVXXJ^XXy^AXXO^QXXXXXXFXy^CXXQ;Xc^BXXG ePXXt^^XzXXb^KXI^CXXXXXX^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^X^XXX^D^A^X^X7^X,^X^X^X^XX^X^V^X^X^FXXXXpH,^ZXOXX^RyXY^XX^XXt:^PYXXXXXXp6^XXMxL.XXXXXzXnXXWXXXXqLXXX5XTXX:^XnXCXDXEXFXGsXIXJs^DvxXOP^BWXZ^X^XXGXYXZXXXE^DX^XXX XXXXXXX^Q^MXPXXRXX\^\XaX\XXXXKXXF^PXXXO1XXZXXWXXXXXDXXX^P^LXXXSXXXAXXgXXX--XXkXXXXXoXXs^Q^KXx1XXXXXBXfXXX^Y^X^XXXXiXX0XXFXXXXC^H^S"XX XXXXXXXXPXKeXX ^F^S00XXXX^BXC^L^T QXXXX-^\
^U,Rt^HXMX^HXVXXXAXh^HXXM8^V^\XXXXXK,XXKdPdXPXXEX^WX2X\XXXXBXX^U,XXX ^AXD^F^VXLXXzuEXK^UVXeXI^V ^EXXR^NXXX^S^SP1B1XXXXXXKX40XXXX.XMXWXXXXXXDXXX,:XXXXXXX6X\X XERXXRXHXXVXXX^XPXXIn-hpXPCXXMXNXXIjXQCX^K^L4^XX8X^FXM^T 2XXX;X^CGXS^MXXXX^CEXXXXXXaXsXXXQk,XXXXL^TXCX^LXXA"cXMXNXXXX^XXXqXXXO^DXXX
XPfX XDXX^XXXXX^SH5bxXQwXX^NXCXXB^KX-XQ^FXXPW^^Y^DX^R\XXM4XXX^TXMFwXXPX^LX^MXXXX2XXX^G^YXX^W^LCXXUj/XXX M^O88XY;^QIXH\9X^X^F^XQ:^RXFXX/X^PXP^L^XXXBX/p^HX "XXX^GXXXXXTX XX^Lz4R^B^B^WXlX^R
2XXXB^L/XXXB^K.XXX^GXX ^C^HOXXXX\XX0 ^MXXX^B^L3XPX^B^G.XxN^D^MXXXel^UXX^XX^XXXE^FXpX^EXXSXNXA^G^XXXX^F^XXuXXX^A2iX XB.XS^Sz^GX7X^VXXXX-^U^Nu^B^M XXSXXTXXX^^AXU XGXXXjH6XXXXBqXPXlo^OH^VXpXX^XXXXXZXCX2XMX
m^V6VXX X2XS-z^R XXX^RHXP^LX^B^G^\XXXXXXN^P^X;QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ

The configure line used to compile these squids is:

    env CC="cc" CFLAGS="-fast -KPIC" \
    ./configure --prefix=/usr/local/squid --enable-cache-digests --enable-snmp \
                --with-aio-threads=32 --with-pthreads --enable-storeio=ufs,aufs,diskd \
                --disable-unlinkd
Received on Thu Sep 19 2002 - 18:57:30 MDT