Re: [PATCH v1 16/20] node_device_udev: Use a worker pool for processing events and emitting nodedev event
On Fri, Apr 19, 2024 at 04:49 PM +0200, Marc Hartmayer <mhartmay(a)linux.ibm.com>
wrote:
Use a worker pool for processing the events (e.g. udev, mdevctl
config changes)
and the initialization instead of a separate initThread and a mdevctl-thread.
This has the large advantage that we can leverage the job API and now this
thread pool is responsible to do all the "costly-work" and emitting the
libvirt
nodedev events.
Signed-off-by: Marc Hartmayer <mhartmay(a)linux.ibm.com>
---
[…snip…]
+ /* must be initialized before trying to reconnect to all the running mdevs
+ * since there might occur some mdevctl monitor events that will be
+ * dispatched to the worker pool */
+ priv->workerPool = virThreadPoolNewFull(1, 1, 0,
nodeDeviceEventHandler,
The more I think about the number of workers in this pool, the more I'm
convinced that it's (currently) important to use only _one_ worker (1
udev thread <-> 1 worker), because otherwise we don't have any
guarantees that we comply to the following:
order(udev_events) == order(libvirt nodedev events)
And I guess we would like to fulfill this guarantee.
If you agree, then we should add a comment to the code and if needed we
can implement something for the case #count > 1.
[…snip]
--
Kind regards / Beste Grüße
Marc Hartmayer
IBM Deutschland Research & Development GmbH
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Geschäftsführung: David Faller
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