MailScanner performance issues

[Zaeem Arshad]

Hi List,

For the past couple of days, my normally fine MailScanner system
started showing signs of sluggishness. At one time, the queue climbed
up to 90,000. We did not observe any sort of spam or other attack
during that period. Since that fateful day, I have tried upgrading the
version from 4.77 to 4.81 but no effect. While I am still trying to
understand why the system is working slow, I have observed that the
queue has more than a 1000 messages but MailScanner processes are
picking up a random number instead of the configured 50 messages. A
log of the processes is available at http://pastebin.com/hgBu66HL. .
For now, I have bypassed MailScanner as the queue buildup is too much
to handle. The incoming workdir is on tmpfs and I haven't seen any
disk or IO issues. Here is the output of MailScanner -version.


MailScanner -version
Running on
Linux antivirus5.cyber.net.pk 2.6.18-128.el5 #1 SMP Wed Jan 21
10:41:14 EST 2009 x86_64 x86_64 x86_64 GNU/Linux
This is CentOS release 5.3 (Final)
This is Perl version 5.008008 (5.8.8)

This is MailScanner version 4.81.4
Module versions are:
1.00    AnyDBM_File
1.30    Archive::Zip
0.23    bignum
1.04    Carp
1.41    Compress::Zlib
1.119   Convert::BinHex
0.17    Convert::TNEF
2.121_08        Data::Dumper
2.27    Date::Parse
1.00    DirHandle
1.05    Fcntl
2.74    File::Basename
2.09    File::Copy
2.01    FileHandle
1.08    File::Path
0.20    File::Temp
0.90    Filesys::Df
3.64    HTML::Entities
3.64    HTML::Parser
3.57    HTML::TokeParser
1.23    IO
1.14    IO::File
1.13    IO::Pipe
2.04    Mail::Header
1.89    Math::BigInt
0.22    Math::BigRat
3.07    MIME::Base64
5.427   MIME::Decoder
5.427   MIME::Decoder::UU
5.427   MIME::Head
5.427   MIME::Parser
3.07    MIME::QuotedPrint
5.427   MIME::Tools
0.13    Net::CIDR
1.25    Net::IP
0.16    OLE::Storage_Lite
1.04    Pod::Escapes
3.05    Pod::Simple
1.09    POSIX
1.19    Scalar::Util
1.78    Socket
2.16    Storable
1.4     Sys::Hostname::Long
0.27    Sys::Syslog
1.26    Test::Pod
0.86    Test::Simple
1.9707  Time::HiRes
1.02    Time::localtime

Optional module versions are:
1.30    Archive::Tar
0.23    bignum
1.82    Business::ISBN
1.10    Business::ISBN::Data
1.08    Data::Dump
1.814   DB_File
1.25    DBD::SQLite
1.607   DBI
1.15    Digest
1.01    Digest::HMAC
2.36    Digest::MD5
2.11    Digest::SHA1
1.00    Encode::Detect
0.17008 Error
0.18    ExtUtils::CBuilder
2.18    ExtUtils::ParseXS
2.38    Getopt::Long
0.44    Inline
1.08    IO::String
1.04    IO::Zlib
2.21    IP::Country
missing Mail::ClamAV
3.002005        Mail::SpamAssassin
v2.004  Mail::SPF
1.999001        Mail::SPF::Query
0.2808  Module::Build
0.20    Net::CIDR::Lite
0.66    Net::DNS
0.002.2 Net::DNS::Resolver::Programmable
missing Net::LDAP
 4.004  NetAddr::IP
1.94    Parse::RecDescent
missing SAVI
2.64    Test::Harness
0.95    Test::Manifest
1.98    Text::Balanced
1.35    URI
0.7203  version
0.62    YAML



Regards

Zaeem