Do you see any zombies? Did you make sure there are no memory leaks in the driver? ----- Original Message ----- From: Martin Maletinsky <maletinsky@scs.ch> To: <kernelnewbies@nl.linux.org> Sent: Monday, February 18, 2002 3:41 PM Subject: Linux under high load > Hi, > > I am writing a device driver. While testing the driver, I run it under high load (i.e. most of the physical memory is allocated by the driver, hundreds of processes > competing for access to the driver interface, which allows 32 processes at a time only). In that situation, the machine 'almost hangs', i.e. input on the terminal is > processed extremly slowly (dozens of seconds up to more than a minute, for a /sbin/lsmod) - this is not surprising, due to both, the lack of available memory as well as the > high number of running processes (moreover the machine is diskless, booting over the network, and has no swap space). > When I kill all the processes that use the driver (with killall), I sometimes observe, that the driver's > usage count does not drop to 0, and that the driver does not release the memory it had allocated (the driver allocates memory on behalf of a process when the process opens > the driver - it releases that memory in the release() method). The symptoms look as if some of the processes would have vanished, without invoking the release() method. > Since I don't observe any such problems or inconsistencies unless running with excessively high load, I was wondering, if that problem might be related to the Linux OS, > rather than to my driver (one possiblity would be that Linux removes some processes under high load, without properly calling the release method for all open files). > Has anyone made similar observations? > > regards > Martin > > -- > Supercomputing System AG email: maletinsky@scs.ch > Martin Maletinsky phone: +41 (0)1 445 16 05 > Technoparkstrasse 1 fax: +41 (0)1 445 16 10 > CH-8005 Zurich > > > -- > Kernelnewbies: Help each other learn about the Linux kernel. > Archive: http://mail.nl.linux.org/kernelnewbies/ > IRC Channel: irc.openprojects.net / #kernelnewbies > Web Page: http://www.kernelnewbies.org/ > > -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/
