> > I'm not sure. > > There is a bug in some kernels where the time stamp of some blocks is > > wrong, so old data doesn't get flushed out by bdflush when it should. > > This can mean that data older than the bdflush interval stays in > > memory until it is forced out by the journal being full. > > > > Maybe your average data rate fills the journal in about 4 minutes, and > > the other bug is interfering with the regular bdflush writeout of data > > blocks. > > > > What kernel are you running? Are you using any ext3 patches on top of > > it? > > Neil, I think the bug you are referring to is fixed by akpm's > introduction of jbd_refile_buffer in fs/jbd/transaction.c. Looking at > the source for Redhat's kernel, I see that that is only fixed in > the current rawhide kernel and as such all RH kernels from 7.3 till RH 9 > would have this bug where buffers hang around longer than the bdflush > kernel and then cause a write storm when the journal is full > > This seems to hurt busy servers a lot > > Maybe Stephen can comment on this more. I'll try to file a bugzilla > report in case this helps to get an errata kernel released The latest RH errata kernel 2.4.20-13 doesn't have this fix incorporated. I guess one has to continue to tweak bdflush params or make regular sync calls to prevent a write storm Regards, Yusuf _______________________________________________ Ext3-users@redhat.com https://www.redhat.com/mailman/listinfo/ext3-users
