SIGQUEUE_MAX's limit of 32 is too low
Taken from the email@example.com list:
On 18 June 2013 19:33, Gary Mills <firstname.lastname@example.org> wrote: > On Tue, Jun 18, 2013 at 07:01:08PM +0200, Cedric Blancher wrote: >> ksh93 -c 'getconf SIGQUEUE_MAX' returns 32 on Illumos but 5632 on Suse >> 12.3 Linux. Does anyone know why the values are so... different? > > $ uname -a > SunOS qtpie 5.11 11.1 i86pc i386 i86pc > $ whence getconf > /usr/bin/getconf > $ getconf SIGQUEUE_MAX > 128 This is still far too low if you wish to use realtime signals for inter-process communication. It defeats the purpose of SIGRTMIN-SIGRTMAX which are supposed to be *reliable*.
The issue is that the SIGQUEUE_MAX limit in Illumos is far to low to be usable. Solaris 11.1 uses 128 and Linux uses 5632.
IMO a limit of at least 32*32, i.e. 1024 would be the minimum acceptable for any application which wishes to use realtime signals (i.e. SIGRTMIN-SIGRTMAX) for reliable and fast interprocess/interthread communication.
AFAIK bumping this limite was forgotten when SUN increased the realtime signals from 8 signals (a joke these days) to 64^H^H32.
Updated by David Höppner about 6 years ago
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