On Mon, Jul 14, 2003 at 11:49:14AM +0930, Greg 'groggy' Lehey wrote: > On Sunday, 13 July 2003 at 20:57:46 -0500, Marc Wiz wrote: > > On Mon, Jul 14, 2003 at 10:02:58AM +0930, Greg 'groggy' Lehey wrote: > >>> I don't believe vinum can optimize full-stripe writes, though, since > >>> FreeBSD can only do I/O in 64k max chunks, > >> > >> 128 kB. > > > > I thought physio was limited to 64 KB? The man page on dump states > > this. Please correct me if I am wrong. > > Physio is limited to MAXPHYS, which you'll find defined in > /usr/include/sys/param.h: > > #ifndef MAXPHYS > #define MAXPHYS (128 * 1024) /* max raw I/O transfer size */ > #endif >
That's nice to know. What prevents it from being increased beyond 128K? > I've taken a look at the dump code (yuk!), and it no longer places any > limitation on the block size. I'll fix the man page. > Thanks. I have tried increasing the block size but going past 64K does not seem to help performance. I will have to check the dump code to see if it is limiting itself to a max of 64K. Thanks! Marc -- Marc Wiz [EMAIL PROTECTED] Yes, that really is my last name. _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
