Slow, what's wa CPU time?

Question

My archLinux sometime is slow when run a few application at the same time.
The following is the top command output: Looks a lot of time is "wa" (IO Wait?) time. And the hard disk seems very busy. How to improve ArchLinux to make it faster? that is, less "wa" time?
Tasks: 132 total,   2 running, 128 sleeping,   0 stopped,   2 zombie
Cpu(s):  7.5% us,  6.2% sy,  0.0% ni,  0.0% id, 85.6% wa,  0.7% hi,  0.0% si
Mem:    383940k total,   381340k used,     2600k free,   102804k buffers
Swap:   385520k total,   302688k used,    82832k free,    32372k cached

Answer 1

tpowa wrote:do you use tmpfs? for /tmp
try to disable tmpfs and use normal /tmp instead
your swap is heavily used
thats quite strange you have 400MB RAM
what kernel you use?
I have 384MB RAM. The kernel is Linux myhost 2.6.7 #1 SMP Wed Jun 16 07:04:51 PDT 2004 i686 unknown unknown GNU/Linux
my /ets/fstab: (am i using tmpfs or /tmp?)
# /etc/fstab: static file system information
# <file system> <dir> <type> <options> <dump> <pass>
none /proc proc defaults 0 0
none /dev/pts devpts defaults 0 0
none /dev/shm tmpfs defaults 0 0
tmpfs /tmp tmpfs defaults 0 0
sysfs /sys sysfs defaults 0 0
usbdevfs /proc/bus/usb usbdevfs defaults 0 0
/dev/cdroms/cdrom0 /mnt/cd iso9660 ro,user,noauto,unhide 0 0
/dev/cdroms/cdrom0 /mnt/dvd udf ro,user,noauto,unhide 0 0
/dev/floppy/0 /mnt/fl vfat user,noauto,unhide 0 0
/dev/discs/disc0/part5 swap swap defaults 0 0
/dev/discs/disc0/part3 / reiserfs defaults 0 0
My hard disk bench test is listed as following. I have an old computer (PII 350, Dell XPS 350 with 15G harddisk, Intel BX chipset motherboard). Is the performance good enough? Or I still need to adjust it?
[root@myhost etc]# for i in 1 2 3 4 5; do hdparm -tT /dev/discs/disc0/disc; done
/dev/discs/disc0/disc:
Timing buffer-cache reads: 416 MB in 2.02 seconds = 206.28 MB/sec
Timing buffered disk reads: 38 MB in 3.16 seconds = 12.02 MB/sec
/dev/discs/disc0/disc:
Timing buffer-cache reads: 416 MB in 2.02 seconds = 206.28 MB/sec
Timing buffered disk reads: 38 MB in 3.09 seconds = 12.30 MB/sec
/dev/discs/disc0/disc:
Timing buffer-cache reads: 416 MB in 2.02 seconds = 205.97 MB/sec
Timing buffered disk reads: 38 MB in 3.09 seconds = 12.29 MB/sec
/dev/discs/disc0/disc:
Timing buffer-cache reads: 412 MB in 2.00 seconds = 205.83 MB/sec
Timing buffered disk reads: 38 MB in 3.13 seconds = 12.15 MB/sec
/dev/discs/disc0/disc:
Timing buffer-cache reads: 416 MB in 2.02 seconds = 206.28 MB/sec
Timing buffered disk reads: 38 MB in 3.12 seconds = 12.19 MB/sec