2.4.21-rc1 VM swaps out too much

2.4.21-rc1 VM swaps out too much

[Rene Rebe]

Hi all,

somewhere in the 2.4.21-xx series (currently running -rc1 here) seems
to be a VM regression, that results in quite hefty swap-outs. The box
is an Athlon-XP with 512MB RAM, running batched gcc jobs (distribution
builds taking three days and more...). But the box is used a normal
workstation, too. My normal desktop programs constantly need to get
swapped-in - quite annoying. This only start to happen after an uptime
of a day.

So the CPU:

vendor_id       : AuthenticAMD
cpu family      : 6
model           : 6
model name      : AMD Athlon(tm) 4 Processor
stepping        : 2
cpu MHz         : 1460.481
cache size      : 256 KB

$ cat /proc/meminfo
        total:    used:    free:  shared: buffers:  cached:
Mem:  527351808 519213056  8138752        0 88793088 328437760
Swap: 537214976 184963072 352251904
MemTotal:       514992 kB
MemFree:          7948 kB
MemShared:           0 kB
Buffers:         86712 kB
Cached:         252328 kB
SwapCached:      68412 kB
Active:         276828 kB
Inactive:       177468 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:       514992 kB
LowFree:          7948 kB
SwapTotal:      524624 kB
SwapFree:       343996 kB

$ uptime
 21:52:41 up 4 days, 23:55,  4 users,  load average: 2.14, 2.47, 2.32

$ cat /proc/version
Linux version 2.4.21-rc1 (root@jackson) (gcc version 3.2.2) #1 Mon Apr 28 00:36:17 CEST 2003

More data available on request.

- René

--  
René Rebe - Europe/Germany/Berlin
e-mail:   rene@rocklinux.org, rene.rebe@gmx.net
web:      http://www.rocklinux.org/people/rene http://gsmp.tfh-berlin.de/rene/

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Re: 2.4.21-rc1 VM swaps out too much

[Rene Rebe]

Hi,

2.5.68 is much smoother, quite less swap is used, my editors are not
pulled out of the swap all the time:

$ free
             total       used       free     shared    buffers     cached
Mem:        515848     505804      10044          0      92808     173876
-/+ buffers/cache:     239120     276728
Swap:       524624      35612     489012

Linux version 2.5.68 (root@jackson) (gcc version 3.2.2) #2 Sun May 4 00:20:13 CEST 2003

20:39:52 up 1 day, 20:17,  2 users,  load average: 3.31, 3.36, 3.19


On: Sat, 03 May 2003 21:55:34 +0200 (CEST),
    Rene Rebe <rene.rebe@gmx.net> wrote:
> Hi all,
> 
> somewhere in the 2.4.21-xx series (currently running -rc1 here) seems
> to be a VM regression, that results in quite hefty swap-outs. The box
> is an Athlon-XP with 512MB RAM, running batched gcc jobs (distribution
> builds taking three days and more...). But the box is used a normal
> workstation, too. My normal desktop programs constantly need to get
> swapped-in - quite annoying. This only start to happen after an uptime
> of a day.
> 
> So the CPU:
> 
> vendor_id       : AuthenticAMD
> cpu family      : 6
> model           : 6
> model name      : AMD Athlon(tm) 4 Processor
> stepping        : 2
> cpu MHz         : 1460.481
> cache size      : 256 KB
> 
> $ cat /proc/meminfo
>         total:    used:    free:  shared: buffers:  cached:
> Mem:  527351808 519213056  8138752        0 88793088 328437760
> Swap: 537214976 184963072 352251904
> MemTotal:       514992 kB
> MemFree:          7948 kB
> MemShared:           0 kB
> Buffers:         86712 kB
> Cached:         252328 kB
> SwapCached:      68412 kB
> Active:         276828 kB
> Inactive:       177468 kB
> HighTotal:           0 kB
> HighFree:            0 kB
> LowTotal:       514992 kB
> LowFree:          7948 kB
> SwapTotal:      524624 kB
> SwapFree:       343996 kB
> 
> $ uptime
>  21:52:41 up 4 days, 23:55,  4 users,  load average: 2.14, 2.47, 2.32
> 
> $ cat /proc/version
> Linux version 2.4.21-rc1 (root@jackson) (gcc version 3.2.2) #1 Mon Apr 28 00:36:17 CEST 2003
> 
> More data available on request.
> 
> - René

- René

--  
René Rebe - Europe/Germany/Berlin
e-mail:   rene@rocklinux.org, rene.rebe@gmx.net
web:      http://www.rocklinux.org/people/rene http://gsmp.tfh-berlin.de/rene/

Anyone sending unwanted advertising e-mail to this address will be
charged $25 for network traffic and computing time. By extracting my
address from this message or its header, you agree to these terms.

Re: 2.4.21-rc1 VM swaps out too much

[Mike Fedyk]

On Mon, May 05, 2003 at 08:40:36PM +0200, Rene Rebe wrote:
> Hi,
> 
> 2.5.68 is much smoother, quite less swap is used, my editors are not
> pulled out of the swap all the time:
> 
> $ free
>              total       used       free     shared    buffers     cached
> Mem:        515848     505804      10044          0      92808     173876
> -/+ buffers/cache:     239120     276728
> Swap:       524624      35612     489012

You will notice that -aa is better and -rmap is even better still.

I can run badblocks on two drives without very much swapping on 192MB with
-rmap15[aeg]