I now have some more information on the performance issue. It appears to be filesystem related. If I format the drive as FAT32 I am getting a transfer rate of approximately 10MB/second. However, if I format it as ext3 I am seeing a transfer rate of only 101KB/second! The only difference is the filesystem and both are clean filesystems.
I formatted the drive with:
mkfs.ext3 -j -L iomega -O dir_index,has_journal,large_file -t ext3 -v /dev/sdc1
mke2fs 1.41.11 (14-Mar-2010) fs_types for mke2fs.conf resolution: 'ext3', 'default' Calling BLKDISCARD from 0 to 1014095872 failed. Filesystem label=iomega OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 61952 inodes, 247582 blocks 12379 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=255852544 8 block groups 32768 blocks per group, 32768 fragments per group 7744 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376
Writing inode tables: done Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 35 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override.
-Aaron
On Friday, January 14, 2011 01:19:04 am Wolfgang Denk wrote:
Dear Aaron Williams,
please always keep the ML on cc:
In message 4D2FA7F0.7020900@caviumnetworks.com you wrote:
It is based off of 2010.09 but I have applied all of the latest USB updates from GIT with the exception of the multiple LUN support (this breaks the SanDisk Cruzer because the Cruzer reports max lun=1). All caches are enabled and this is on a 1.2GHz MIPS which is cache-coherent (no need to flush/invalidate).
Maybe there are other issues with your code. It's hard to comment on onknown out-of-tree ports.
Best regards,
Wolfgang Denk