I tried 'make -j zdisk' on 1.3.89 sources. After about 8 min of
compilation, the swap usage suddenly shot up above the limit,
compilation choked and make exited. The sudden 3x increase in the
swap usage may be a legitimate event, though looks awfully strange,
but what really alarms me, is that after this the memory and swap
utilization reported by 'top' where ~8.5 Mb and ~11.5 Mb respectively,
which sums up to ~19 Mb, exactly what is reported when the system
comes up after rebooting. Moreover, 'ps -u' told that there are 2(two)
xdm running, and both of them (along with a bunch of other stuff)
are swapped out.
It seems to me that under no circumstances the second xdm should
have been spawned, and, arguably, whatever is swapped out to
disk should be returned to the physical memory as soon as it becomes
available. I've communicated earlier that after uptime reaches couple
of hours, swap used is > 0 even when there is free memory available.
It was not the case with 1.3.20. I am still curious to hear whether
it is a bug or a feature.
Alex Krimkevich.