> Well they do. The Flash disk I have (SATA-I) is capable of 48 MB/s and this > value is reached over the whole disk size by windows as well as by FreeBSD. > See my test results in the first thread.
Ok a flash disk should be more stable > My Seagate Barracuda Harddisk drive (SATA-II) starts with 76 MB/s and > decreases linearly to 35 MB/s due to the fact that it has to write to a > rotating disk. But on a flash disk there is nothing rotating... The hard disk one isn't guaranteed or stable but the flash especially if it is aimed at it ought to behave. > So where is the difference between SATA-I and SATA-II ? All physical side if they are on the same controller when you do the tests. Mostly latency, > And why is FreeBSD able to write with constant rates (the complete 25 GB, all > with 48+/-0.1 MB/s) but Linux 2.6.18 not ? Does the FreeBSD fsync sync to media ? Also what controller is being used here, and do you have EHCI USB support running ? > With a dedicated (rotating) SATA II device, using the first 70% of disk space > no problem -- tested ! With a SATA-I device only a problem with Linux 2.6.18 I suspect the SATA-1 itself may not be the decider but something else - eg the hard disk using NCQ, which would cover up any latency related problems. > Journaling of data: you are right, ext2 performs better than ext3. And ext3 in writeback mode ought in theory (but practice is always harder ;)) be faster than ext2. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/