Hi Tim, Am 16.10.2008 18:04 Uhr, Tim Mancour schrieb: > I added a rdns regexp matching to my qmailtoaster a few years ago and I have > not noticed any performance issues. You do, however, have to make sure that > you keep the number of expressions do to a minimum set (my list of > expressions is currently around 50 lines long). I think this might depend on the mail volume your server has to handle. If you handle a million mails today it surely makes a difference wether you spend +/-100ms per mail, whereas if your server is mostly idle and handles 100.000 mails a day it shouldn't really matter. It is generally said that simple string operations (strstr/strpos) are faster than regular expressions, but I have no hard numbers to back this up, so it'd be interesting to the some numbers on how the processing speed for similar matches compares.
It certainly would make the matching code in spamdyke eg. for matching the IP in an RDNS entry would be much more compact (and IMHO more readable) as those matches could be done in very fewrules as compared to many repetitious rules with small mutations as it is now. -- Felix > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Felix Buenemann > Sent: Thursday, October 16, 2008 11:23 AM > To: [email protected] > Subject: Re: [spamdyke-users] spamdyke > +ip-in-rdns-keyword-blacklist-entryoption > > Am 15.10.2008 15:20 Uhr, Tim Mancour schrieb: >> Sam, >> >> There is a set of POSIX compatible regular expression functions >> available in "C". The functions regcomp() and regexec() are both used >> by qmail to provide regexp testing for the control/badxxxxx files. > > I jusrt wrote a similar mail, as I was wondering why NOT to use regexes in > spamdyke, my only idea was that it could hurt performance. > > There is the PCRE library which enable parsing of perl compatible regular > expressions, which have IMHO the cleanest and most widely used regex syntax. > It's also very easy to test those regexes using perl. > >> Regards, >> Tim > > -- Felix _______________________________________________ spamdyke-users mailing list [email protected] http://www.spamdyke.org/mailman/listinfo/spamdyke-users
