I/O terribly slow - Raspberry Pi Forums

i'm running few things on raspberry pi, , 1 of them irc bot. have noticed of times when script has read/write -- not every time, though -- from/to sd card, script hang 10 20 seconds, before begins reading/writing. have noticed same when running commands. works, , other times have wait 10 seconds start running command (ls or pacman example).
i'm running arch linux on 16 gb class 4 sd card.

read-only benchmark:

[raspberrypi@raspberryrobin ~]$ sudo hdparm -tt /dev/mmcblk0

/dev/mmcblk0:
timing cached reads: 304 mb in 2.01 seconds = 151.59 mb/sec
timing buffered disk reads: 44 mb in 3.10 seconds = 14.21 mb/sec

load averages:

[raspberrypi@raspberryrobin ~]$ uptime
15:03:05 5 days, 17:01, 2 users, load average: 1.59, 2.19, 2.01

average cpu usage 4%, while average ram usage 32mb figured can't else i/o. problem noticable when script needs run simple insert query sqlite database. script hang 20 seconds until query completes, , continue if nothing special has happened.

... nobody?

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