2.0.1 memory management

Mikkel Lauritsen (c918531@student.dtu.dk)
Mon, 8 Jul 1996 12:27:24 +0200 (METDST)

Hi, all

Yesterday I had a small (?) rendering program running on one of my
machines - 64 MB ram, Linux 2.0.1. The program should allocate about 59
megs of memory, to which top seemed to agree.

1. Why does the program cause Linux to use almost 50 megs of swap space?
No other processes were doing anything at all so they could be (and were,
according to top) removed from physical memory.

2. More seriously, the user process locked the computer, so nobody were
able to run other programs - or even log in. When at first I found that I
wasn't able to telnet to the box I tried to log in as root at the
console, but no go: "Process ID n respawning too fast ..." followed by
"Out of memory, couldn't load libc.so" (or words to that effect). The
offending program was reniced by 14, BTW.

Is the behavior described above a bug or a kernel feature - that is, is
there any way for me to make sure that I'm always able to log in even if
a user process is hogging all available memory? It seems pretty serious
to me that the kernel allows a user process to create a complete lockout
of all other processes.

Mikkel Lauritsen,