Swap (and low memory) performance

[GreyGeek]

Another possibility is IRQ problems. Powertop should help determine how your interrupts are working.
Here's mine:

226 wakeups/second
      0.8 ms/s      61.2        Timer          tick_sched_timer
             15.8 ms/s      24.8        Process        /usr/bin/ksysguard
            128.4 µs/s      19.3        kWork          ieee80211_iface_work
              3.6 ms/s      10.3        Process        /usr/bin/X :0 vt7 -br -nolisten tcp -aut
              1.4 ms/s       9.8        Process        dbus-daemon --system --fork --activation
            278.7 µs/s      10.0        Process        /usr/sbin/bumblebeed --use-syslog
             95.2 µs/s       8.3        Process        [rtsx-polling]
            197.8 µs/s       7.7        Timer          hrtimer_wakeup
              1.1 ms/s       7.1        Process        kwin -session 101b7188189177000134408930
              2.3 ms/s       6.2        Process        /usr/bin/python -O /usr/share/wicd/daemo
              6.3 ms/s       4.1        Process        ksysguardd
              0.9 ms/s       5.9        Interrupt      [6] tasklet(softirq)
            144.6 µs/s       4.8        Process        [ksoftirqd/4]
              0.9 ms/s       4.3        Process        /usr/bin/python -O /usr/share/wicd/daemo
              1.7 ms/s       2.7        Process        /usr/bin/plasma-desktop
            378.4 µs/s       2.4        Process        /usr/bin/konsole
            186.9 µs/s       2.2        Process        /usr/sbin/mysqld --defaults-file=/home/j
             84.4 µs/s       2.0        Process        /usr/lib/chromium-browser/chromium-brows
              1.9 ms/s       1.2        Process        wicd

[SecretCode]

This problem seems to have stopped for me. For a while at least!

... I find that it's when paging out/in is taking place that the system grinds to a halt. ...

Keen to hear from others as well, if anyone finds that performance is bearable when the system starts swapping.

It occurred to me that I hadn't experienced such an usable slowdown for a while - but nevertheless I was using some swap - and of course there was some performance impact, but no more than regular IO. Presumably some kernel update has fixed some specific issue. I certainly haven't done anything concrete to address it.

[luckyone]

As noted an SSD gives great bang for the buck. However some dx'ing is needed per the swap usage. I regularly run three different Browsers with 4 to 8 tabs open, a VM, at least one instance of Dolphin. And probably a partridge in a pear tree if I bothered to look closely. I have never seen more than 3.4 GB of my 4 GB of RAM used. I have yet to see swap (a partition) used at all. Zero. Zilch. Nada. I run KDE all the time. I have an old PC. I'm very happy with the responsiveness of my system except for the amount of time that it takes to give me a logon after a lock either a manual one or a screensaver one. It takes a couple of seconds.
I am still running HDDs, both 7200 rpm. Both SATA II.

Of course I'm getting slower also, but that's for another thread.

[SteveRiley]

The only reason I keep a swap partition is for hibernation.

[vinnywright]

my swap partition gets used quite often ,,,, just watching a vid or DVD will use a little and when recoding audio/video .
my system has 4Gig of RAM
see just got done watching a 3+ Hr DVD

vinny@Vinnys-HP-G62:~$ free
total used free shared buffers cached
Mem: 3844396 3619436 224960 0 2020184 495592
-/+ buffers/cache: 1103660 2740736
Swap: 4096536 2384 4094152

VINNY