> MESSAGE-DESERIALIZER-POOL 1 682008 1818682
On the (unverified by me) assumption that disk reads en up in this stage as Anthony indicates, and looking at the above line and the iostat output, makes me want to suggest that maybe the read concurrency is set to 1 and you need to increase it in order to fully utilize your disks. That said, I have no idea why you would have as many as 682 THOUSAND pending for that stage (but I'm not sure at what granularity these are scheduled so perhaps it is normal for e.g. big slicing reads? I don't know.). -- / Peter Schuller
