excessive swap-in time

I sometimes encounter swap-in times for some heavy processes (usually the
Firefox browser) that can take a few MINUTES to complete. Reading all of
the swap space sequentially only takes 40 seconds. I think what really
is happening is that the process is swapping back out as it needs space
to swap in, even though the total VM size is less than half of real RAM.

It would be nice if there was a "swap trace" feature whereby I could see
the swapping actions taking place. Of course it could be a problem as the
process reading such a trace would affect things. I'd like to know how
often the same page has to get swapped in over and over.

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2008-03-13-2018@xxxxxxxx |
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Relevant Pages

  • Re: excessive swap-in time
    ... Trying to do it all with RAM is just inefficient. ... I find that does not work well when the swapping is caused by excessive I/O ... Or you could have 5 TB of swap space. ...
    (comp.os.linux.development.system)
  • Summary swap rules.
    ... So it looks as if swap is mostly not used anymore and can be kept pretty ... Tim Bradshaw stated what I privately felt- that 1:1 swap to memory is ... so it's really only around for memory leaks and core dumps. ... think) which are written to swap space. ...
    (SunManagers)
  • Re: malloc does not return null when out of memory
    ... >> actual RAM and swap are exhausted. ... Having actually worked on the IRIX VM system, and on vswap ... Adding Virtual Swap Space ... You can create a normal file of larger than 0 length and allocate it as ...
    (freebsd-stable)
  • RE: Where do you put your swap partition?
    ... so I can mount /tmp on a tmpfs file system. ... it, hits the disk several times, even with a large buffer cache. ... don't have enough ram, you have to swap, but you're no worse off than ... disk and /var on a third, and have swap space defined on all three. ...
    (Debian-User)
  • Re: Is Greenspun enough?
    ... the swap copy can be liberated. ... This means that whatever swap space you configure nicely ... If you have a gigabyte of RAM, ... >gigabyte VM with one gigabyte of RAM, you need two gigabytes of disk ...
    (comp.lang.lisp)