For what is worth these are the results on my Lenovo Thinkpad T500 with zfs. http://global.phoronix-test-suite.com/?k=profile&u=thuglife-5875-16786-4629
> dmesg | grep ada0 ada0 at ahcich0 bus 0 scbus0 target 0 lun 0 ada0: <WDC WD2500BEKT-00A25T0 01.01A01> ATA-8 SATA 2.x device ada0: 300.000MB/s transfers (SATA 2.x, UDMA6, PIO size 8192bytes) ada0: Command Queueing enabled ada0: 238475MB (488397168 512 byte sectors: 16H 63S/T 16383C) zfs prefetch off zfs checksum on | fletcher4 zfs compression on | lzjb vfs.zfs.arc_min="64M" vfs.zfs.arc_max="512M" stock ufs FBSD http://www.phoronix.com/scan.php?page=article&item=linux_bsd_opensolaris&num=6 Apples and oranges, I know, the point is I don’t feel that the IO performance is lagging on my laptop. On Tue, Feb 9, 2010 at 9:33 AM, krad <kra...@googlemail.com> wrote: > On 9 February 2010 01:54, J65nko <j65...@gmail.com> wrote: > >> On Mon, Feb 8, 2010 at 5:46 AM, alex <a...@mailinglist.ahhyes.net> wrote: >> >> >> > I do suspect personally that the ext4 filesystem is the reason for the >> > difference here, since ext4 has a number of features such as deferred >> disk >> > writes etc. Even deleting a large file off that raid array I can see a >> > difference, prior to reformatting, i deleted a 190GB file off the raid, >> > under UFS the delete took quite some time (well over 10 seconds), under >> ext4 >> > the deletion of the same size file took about 3 seconds. >> > >> > But what I said with ext4 being faster then the aging UFS still rings >> true >> > in my mind, look at the recent Phoronix benchmarks for yourself and see >> (10 >> > pages of benchmarks). >> > >> > >> http://www.phoronix.com/scan.php?page=article&item=freebsd8_benchmarks&num=1 >> > (skip to page 7 of the benchmarks if you want to see the I/O stuff >> relating >> > to disk performance) >> >> According to the first page they used the default configuration of all >> benchmarked OS'es. >> And what is the default mount option on Linux "async" >> >> The FreeBSD man page for mount describes this "async" option as follows: >> >> async All I/O to the file system should be done asynchronously. >> This is a dangerous flag to set, since it does not guar- >> antee that the file system structure on the disk will >> remain consistent. For this reason, the async flag >> should be used sparingly, and only when some data recov- >> ery mechanism is present. >> >> >> The OpenBSD man page has the following additional remark: >> >> The most common use of this flag is to speed up >> restore(8) where it can give a factor of two speed in- >> crease. >> >> Conclusion: you cannot compare filesystem performance, when you give >> one a unfair speed advantage of what could be a factor two. >> _______________________________________________ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to " >> freebsd-questions-unsubscr...@freebsd.org" >> > > > you are of course entirely correct, however one of the goals of more modern > file systems eg ext4 is to make async safe to use, because of this speed up. > At the end of the day faster is faster simple as. Having said that it would > be nice to see a gjournaled ufs system for comparison, as well as zfs > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" > _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
