Date: Sun, 14 Mar 2010 19:57:20 +0300 From: Solar Designer <solar@...nwall.com> To: john-users@...ts.openwall.com Subject: Re: problem with initializing mpirun extended On Sat, Mar 13, 2010 at 09:47:27AM +0100, Magnum, P.I. wrote: > The MPI patch seems to make the buffering of logging more noticable. Why is that? I think it should be taking about as much time (real time, not CPU time) until the first log flush as it does without the patch. > If you start a job in background, the check the logs, it may > very well stop after the "748892 preprocessed word mangling rules" line > you mention for a very long time. But if you issue a kill -HUP to that > process, it will flush its log buffer and you'll see it is in fact working. I think the same would be happening with a single process. There was a relevant change between 1.7.4 and 188.8.131.52 - LOG_BUFFER_SIZE was increased from 4 KB to 32 KB. Maybe this confused you into thinking that MPI had something to do with the change in behavior you've observed. > I have considered flushing more often but I'm not sure how/when to do it > without risking introducing performance hits. Rather than reduce LOG_BUFFER_SIZE, which may hurt performance with a lot of passwords getting cracked quickly or with a lot of rules and a small wordlist, you may lower the "Save" setting in john.conf - say, going from 600 down to 60 seconds won't affect performance significantly. > The current behaviour is as it comes from mpi10. I don't see it in the code. Alexander
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.