My powerful Linux desktop (12 core, 32GB RAM, SSD, fast processor, ubuntu 13.10) slows down to a crawl when I rsync from my internal drive to an attached USB3 NTFS drive. Typing any command, like "df" or "ls", takes 5-10 seconds to respond. The slow feel reminds me of a heavily swapping computer, but the "free" command says swap size is zero, with 29GB of RAM free (buffers). "uptime" shows a load average of about 4.0, and "top" shows that the top processes are the rsync commands. I also see kswapd0 in the top few processes, but no swap space is being used and there's tons of free RAM.
The slowdown occurs even when I run rsync at a "nice" level of 19. The slowdown also lasts for about 1-2 minutes after I kill the rsync.
The slowdown doesn't happen with my other ext4 USB3 disk.
The actual transfer rate to the USB disk is fine: it is not slow. I'm asking about the heavy impact on the usability of the system during the rsync. Anybody know why this happens and how to prevent it?
Some disk info on the USB disk:
$ sudo hdparm -acdgkmurABCMNQW /dev/sdi1 /dev/sdi1: multcount = 0 (off) readonly = 0 (off) readahead = 256 (on) geometry = 364799/255/63, sectors = 5860507648, start = 16384 drive state is: active/idle look-ahead = 1 (on) write-caching = 1 (on) APM_level = 128 acoustic = not supported max sectors = 5860533168/5860533168, HPA is disabled
I omitted these errors from the above output, presumably from unsupported features:
HDIO_GET_32BIT failed: Invalid argument HDIO_GET_UNMASKINTR failed: Invalid argument HDIO_GET_DMA failed: Invalid argument /sys/block/sdi/sdi1/device/queue_depth: No such file or directory HDIO_GET_KEEPSETTINGS failed: Invalid argument