Re: AW: [Xenomai-help] delete queues offline; /proc/stat
[EMAIL PROTECTED] wrote: when a xenomai-task crashs which created some queues (rt_queue_create) and I try to restart the task the creation of the queues will fail as the queue still exists (error EEXIST == 17). Is there a possibility to see which queues exist (I did not find a hint in the /proc/xenomai directory) and to get rid of these queues (or geneally spoken : to get rid of allocated resources) e.g. with a commandline tool ? Native or posix skin? Gilles added per-process resource cleanup to the posix skin in 2.2-rc3. following Murphys law, I, of course, use native skin where this mechanism isn´t implemented yet ;-) What does per-process resource cleanup mean ? When the process/thread is killed the queues and other resources of this process/thread are deleted automaticaly ? Yes, all resources specific to a process are deleted automatically, so, any message queue descriptor or shared memory descriptor is closed. Named objects are not deleted though, since they may be shared between several processes, only non-pshared anonymous objects and named objects *descriptors* are deleted. This is the only reasonable implementation I could find. -- Gilles Chanteperdrix. ___ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
Re: AW: [Xenomai-help] delete queues offline; /proc/stat
Gilles Chanteperdrix wrote: [EMAIL PROTECTED] wrote: when a xenomai-task crashs which created some queues (rt_queue_create) and I try to restart the task the creation of the queues will fail as the queue still exists (error EEXIST == 17). Is there a possibility to see which queues exist (I did not find a hint in the /proc/xenomai directory) and to get rid of these queues (or geneally spoken : to get rid of allocated resources) e.g. with a commandline tool ? Native or posix skin? Gilles added per-process resource cleanup to the posix skin in 2.2-rc3. following Murphys law, I, of course, use native skin where this mechanism isn?t implemented yet ;-) What does per-process resource cleanup mean ? When the process/thread is killed the queues and other resources of this process/thread are deleted automaticaly ? Yes, all resources specific to a process are deleted automatically, so, any message queue descriptor or shared memory descriptor is closed. Named objects are not deleted though, since they may be shared between several processes, only non-pshared anonymous objects and named objects *descriptors* are deleted. This is the only reasonable implementation I could find. What about a usage counter maintained on creation/binding vs. closing/destruction? I would prefer to get them cleaned up automatically as well somehow, or we really need tool support for IPC cleanup, and that is ugly in my eyes. Jan signature.asc Description: OpenPGP digital signature ___ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
Re: AW: [Xenomai-help] delete queues offline; /proc/stat
Jan Kiszka wrote: Yes, all resources specific to a process are deleted automatically, so, any message queue descriptor or shared memory descriptor is closed. Named objects are not deleted though, since they may be shared between several processes, only non-pshared anonymous objects and named objects *descriptors* are deleted. This is the only reasonable implementation I could find. What about a usage counter maintained on creation/binding vs. closing/destruction? I would prefer to get them cleaned up automatically as well somehow, or we really need tool support for IPC cleanup, and that is ugly in my eyes. I am not sure one would expect a named object to be unlinked when one only calls its close service, without calling its unlink service. If, on the other hand, one calls the unlink service, then the object will be automatically destroyed when the last descriptor is closed, as mandated by the specification. Moreover, the existence of such objects is not a leak that will grow over time, if one do not use the O_EXCL flag when opening objects, existing objects will simply be reused. If one use the O_EXCL flag, opening will fail. This behaviour is the same as Linux behaviour. -- Gilles Chanteperdrix. ___ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
Re: AW: [Xenomai-help] delete queues offline; /proc/stat
On Thu, 2006-07-06 at 13:59 +0200, Gilles Chanteperdrix wrote: Jan Kiszka wrote: Yes, all resources specific to a process are deleted automatically, so, any message queue descriptor or shared memory descriptor is closed. Named objects are not deleted though, since they may be shared between several processes, only non-pshared anonymous objects and named objects *descriptors* are deleted. This is the only reasonable implementation I could find. What about a usage counter maintained on creation/binding vs. closing/destruction? I would prefer to get them cleaned up automatically as well somehow, or we really need tool support for IPC cleanup, and that is ugly in my eyes. I am not sure one would expect a named object to be unlinked when one only calls its close service, without calling its unlink service. If, on the other hand, one calls the unlink service, then the object will be automatically destroyed when the last descriptor is closed, as mandated by the specification. I agree with this interpretation. Think of some application loader process that just creates the basic infrastructure, like shared mem segs, then exits, leaving the actual use of such resources to some other processes. I did see this a few times in customer designs. Moreover, the existence of such objects is not a leak that will grow over time, if one do not use the O_EXCL flag when opening objects, existing objects will simply be reused. If one use the O_EXCL flag, opening will fail. This behaviour is the same as Linux behaviour. -- Philippe. ___ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
