Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Thu, 2006-04-13 at 16:26 +0200, Philipp Reisner wrote: > Hi, > > Actually my gut feeling was that drbd-8.0 would perform > better than drbd-0.7.17, since it allows and uses BIOs > up to 32KB of data, while the 0.7 code only allows up > to 4KB of data in a single BIO (that is caused by the > Linux-2.4.x compatibility) > > But on recent hardware, the CPU is so fast that the bigger > BIOs bring no measurable advantage. > Thanks for the comparison. How much difference was there in cpu usage? Best regards, Umberto > > CPU: Intel(R) Pentium(R) D CPU 3.20GHz > ram: 2G > IO subsystem: 3ware Inc 9xxx-series SATA-RAID > Kernel: rhas4(centOS) 2.6.9-22.EL > > [root at node2 tmp]# /root/dm -a 0 -o testfile -s 1G -y -m -p -b 1M > > version: 8.0pre2a (api:81/proto:80) > SVN Revision: 2144M build by root at baumeister, 2006-04-12 11:17:47 > > Full sync: > drbd0: Resync done (total 4372 sec; paused 0 sec; 41388 K/sec) > drbd0: Resync done (total 3995 sec; paused 0 sec; 45296 K/sec) > > with filesystem (dm -a 0 -o testfile -s 1G -y -m -p -b 1M): (outer cylinders?) > 33.11 MB/sec (1073741824 B / 00:30.930201) > 32.06 MB/sec (1073741824 B / 00:31.941736) > 32.29 MB/sec (1073741824 B / 00:31.712577) > > w/o FS (inner cylinders) > 52.30 MB/sec (1073741824 B / 00:19.579340) > 54.06 MB/sec (1073741824 B / 00:18.941363) > 53.76 MB/sec (1073741824 B / 00:19.047350) > > version: 0.7.17 (api:77/proto:74) > SVN Revision: 2093 + GFP_NOIO fix build by root at baumeister, 2006-03-13 > 13:19:09 > > w FS (dm -a 0 -o testfile -s 1G -y -m -p -b 1M): (outer cylinders?) > 33.01 MB/sec (1073741824 B / 00:31.020205) > 32.55 MB/sec (1073741824 B / 00:31.454737) > 32.71 MB/sec (1073741824 B / 00:31.303779) > > w/o FS (inner cylinders) > 54.13 MB/sec (1073741824 B / 00:18.916885) > 54.50 MB/sec (1073741824 B / 00:18.788823) > 53.22 MB/sec (1073741824 B / 00:19.240387) > > -Philipp -- Umberto Nicoletti | We are Pentium of Borg. +390415701366 unicoletti at prometeo.it | Division is futile. Prometeo S.R.L. The Software Experience | You will be approximated.