On Oct 23, 2012, at 4:07 AM, Pavel Machek wrote: > Hi! > >> As requested, I compared performance of VFAT with f2fs on SD card. >> Following is summary of the measurement. > > Thanks. > >> VFAT shows better performance on both random write+fsync and >> buffered-sequential write than f2fs. >> However, on buffered-random and sequential write+fsync, f2fs still exhibits >> better performance >> than other filesystems. >> >> >> * buffered write (1GB file), 4KByte write >> ------------------------------------------------------------------------------ >> Desktop PC Galaxy-S3 >> ------------------------------------------------------------------------------ >> sequential (MB/s) random (IOPS) sequential (MB/s) random (IOPS) >> ------------------------------------------------------------------------------ > ... >> F2FS 10.6 2675 6.9 1682 >> VFAT 7.3 1108 7.3 1075 >> >> ------------------------------------------------------------------------------ > > Ok, f2fs is bit faster on desktop PC and a bit slower on S3. Good. > > >> * write + fsync (100MB file), 4KByte write >> ------------------------------------------------------------------------------ >> Desktop PC Galaxy-S3 >> ------------------------------------------------------------------------------ >> sequential (KB/s) random (IOPS) sequential (KB/s) random (IOPS) >> ------------------------------------------------------------------------------ >> F2FS 1057.9 240 772.3 184 >> VFAT 356.5 260 474.4 373 >> ------------------------------------------------------------------------------ > > Ok, random access on VFAT is a lot faster on S3 (and only very > a bit on PC). Any idea why results are so different between PC and S3? > Does F2FS need significantly more CPU? Does F2FS need significantly > more RAM? (Booting PC with low mem= option my answer that). >
Yes, I think that f2fs really needs more CPU and memory for functioning. The f2fs keeps more metadata as VFAT, as I understand. Moreover, it manages six active logs at runtime and GC can works in background. All of it needs in more CPU power. With the best regards, Vyacheslav Dubeyko. > Anyway, it looks like F2FS is pretty fast filesystem... > > Pavel > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) > http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
