[opensuse] top's PID field width maximum=5?
I can't seem to find a way to increase it to 6 so that wraps less often. -- "The wise are known for their understanding, and pleasant words are persuasive." Proverbs 16:21 (New Living Translation) Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata *** http://fm.no-ip.com/ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On 11/09/2016 02:14 PM, Felix Miata wrote:
I can't seem to find a way to increase it to 6 so that wraps less often.
And what is that high value that has more than 6 digits? Oh, right, you're on a 64-bit machine so you can have PID that is more than 32K. Ha ha ha. No, really. On 64-bit machines you can set the PID_MAX_LIMIT to some BIGNUM. But why should you? The idea is to have a unique PID for each process and, hopefully, the re-use of the PIDs as they cycle round taking a reasonable time so as not to cause confusion. A big enough number and we can think in geological ages. But why? Certainly on a home PC or a simple server we've been OK with the 32K limit. And a heavily interactive PC is probably going to see more process creation, more thread creation, than, say, a SAN server running NFS or SAMBA. So yes, if you have PID_MAX_LIMIT set to a number that may well go over 99,999 (0x1869F, 1 1000 0110 1001 1111) but still be (17-bits) within the range of a 32-but register. IF AND ONLY IF you have PID_MAX_LIMIT set that high. Overflowing a 32-bit register, well BIGNUM is now (2^31)+1 No, that would break the virtual memory manager, the limit is really 2^22 Have you any idea what your PID_MAX_LIMIT is set to? Try looking in /proc/sys/kernel/pid_max (I believe that came about in 2.5.37) Mine, on a 13.2 64-bit system is set to 32768 -- A: Yes. > Q: Are you sure? >> A: Because it reverses the logical flow of conversation. >>> Q: Why is top posting frowned upon? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Anton Aylward composed on 2016-11-09 15:10 (UTC-0500):
Have you any idea what your PID_MAX_LIMIT is set to?
$ cat /proc/sys/kernel/pid_max 32768 $ ps -A | egrep 'onk|efox' 2369 ? 1-05:14:34 seamonkey 10620 ? 04:11:41 seamonkey 16401 ? 00:22:50 firefox 25651 ? 03:02:49 firefox 25764 ? 00:05:57 firefox-bin Question 1: on which virtual desktop is a mozilla instance is pegging the CPU? Question 2: which PID belongs to the mozilla instance that is more slothful when the CPU%s are jumping around and more than one is not consistently low? ATM I happen to remember that 2369 is the only one not restarted since login, but once I've restarted each at least once, I can't tell which is which. A 6th digit would considerably delay the wrap, making it easier to tell which is which. -- "The wise are known for their understanding, and pleasant words are persuasive." Proverbs 16:21 (New Living Translation) Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata *** http://fm.no-ip.com/ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Felix Miata wrote:
Have you any idea what your PID_MAX_LIMIT is set to?
$ cat /proc/sys/kernel/pid_max 32768
So, just set pid_max to 99999 on boot. (at boot time: echo "99999" >/proc/sys/kernel/pid_max) That gives you more headroom, w/o worrying about field with problems. apropos 'sysctl' and look at things under sections 8 and 5 for official ways to do this.. ;-) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
participants (3)
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Anton Aylward -
Felix Miata -
Linda Walsh