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authorThomas Schwinge <tschwinge@gnu.org>2013-04-07 18:18:44 +0200
committerThomas Schwinge <tschwinge@gnu.org>2013-04-07 18:18:44 +0200
commit6c7d45e4631784d0e077e806521a736da6b0266e (patch)
treef9d3e9ed304e8cdbf72fc77c135781eb49990f6a /open_issues/nice_vs_mach_thread_priorities.mdwn
parentf8ed211a4da23edf469089254b3dace9479bf11f (diff)
IRC.
Diffstat (limited to 'open_issues/nice_vs_mach_thread_priorities.mdwn')
-rw-r--r--open_issues/nice_vs_mach_thread_priorities.mdwn40
1 files changed, 40 insertions, 0 deletions
diff --git a/open_issues/nice_vs_mach_thread_priorities.mdwn b/open_issues/nice_vs_mach_thread_priorities.mdwn
index e27d3018..1f4c6ab8 100644
--- a/open_issues/nice_vs_mach_thread_priorities.mdwn
+++ b/open_issues/nice_vs_mach_thread_priorities.mdwn
@@ -387,3 +387,43 @@ here.
<youpi> the issue is mach not supporting enough sched levels
<youpi> can be fixed, of course
<youpi> just nobody did yet
+
+GNU Mach commit 6a234201081156e6d5742e7eeabb68418b518fad (and commit
+6fe36b76f7983ec9a2e8a70420e431d54252442e).
+
+
+## IRC, OFTC, #debian-hurd, 2013-03-07
+
+ <braunr> youpi: btw, why did you increase the number of priorites to 50 ?
+ <youpi> for the nice levels
+ <braunr> and probably something more, there are only 40 nice levels
+ <youpi> yes, the current computation leaves some margin
+ <youpi> so I preferred to keep a margin too
+ <braunr> ok
+ <youpi> e.g. for the idle thread, etc.
+ <braunr> or interrupt threads
+ <youpi> yep
+ <braunr> i see the point, thanks
+ <tschwinge> Is the number of 40 specified by POSIX (or whatever) or is that
+ a Linuxism?
+ <braunr> good question
+ <braunr> posix is weird when it comes to such old unixisms
+ <braunr> there is a NZERO value, but i don't remember how it's specified
+ <youpi> it's at least 20
+ <tschwinge> (I don't object to the change; just wondered. And if practice,
+ you probably wouldn't really need more than a handful. But if that
+ change (plus some follow-up in glibc (?) improves something while not
+ adding a lot of overhead, then that's entirely fine, of course.)
+ <braunr> "A maximum nice value of 2*{NZERO}-1 and a minimum nice value of 0
+ shall be imposed by the system"
+ <braunr> NZERO being 20 by default
+ <youpi> and 20 is the minimum for NZERO too
+ <braunr> hm, not the default, the minimul
+ <braunr> minimum
+ <braunr> yes that's it
+ <braunr> ok so it's actually well specified
+ <tschwinge> Aha, I see (just read it, too). So before that change we
+ simply couldn't satisfy the POSIX requirement of (minimum) NZERO = 20,
+ and allowing for step-1 increments. Alright.
+ <youpi> yep
+ <youpi> thus failing in coreutils testsuite