On Fri, 12 Feb 2016, Markus Blank-Burian wrote: > Hi, > > I had an issue with major CPU usage on several OSDs. Looking further into > this matter it turned out, that the tiering agent was iterating directories > over and over. The metadata was all cached, so there was no disk activity. > > If we have e.g. flush-mode low and evict-mode idle, then there are only > osd_agent_max_low_ops concurrent requests allowed, but the check in > OSDService::agent_entry only waits, if agent_ops >= osd_agent_max_ops. It > would be straight forward to add an additional check for > osd_agent_max_low_ops. Would there be any issues with the modifications in > the attached patch? That sounds reasonable to me. Does it address the core problem though? It sounds like what we really need is to limit the amount of non-op work the agent does... sage -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
