Re: [PATCH 7/8] blk-mq: create hctx for each present CPU

2017-06-08 Thread Christoph Hellwig
On Wed, Jun 07, 2017 at 03:04:11PM -0700, Omar Sandoval wrote: > On Sat, Jun 03, 2017 at 04:04:02PM +0200, Christoph Hellwig wrote: > > Currently we only create hctx for online CPUs, which can lead to a lot > > of churn due to frequent soft offline / online operations. Instead > > allocate one

Re: [PATCH 7/8] blk-mq: create hctx for each present CPU

2017-06-07 Thread Omar Sandoval
On Sat, Jun 03, 2017 at 04:04:02PM +0200, Christoph Hellwig wrote: > Currently we only create hctx for online CPUs, which can lead to a lot > of churn due to frequent soft offline / online operations. Instead > allocate one for each present CPU to avoid this and dramatically simplify > the code.

Re: [PATCH 7/8] blk-mq: create hctx for each present CPU

2017-06-07 Thread Christoph Hellwig
On Wed, Jun 07, 2017 at 05:10:46PM +0800, Ming Lei wrote: > One thing not sure is that we may need to handle new CPU hotplug > after initialization. Without the CPU hotplug handler, system may > not scale well when more CPUs are added to sockets. Adding physical CPUs to sockets is a very rare

Re: [PATCH 7/8] blk-mq: create hctx for each present CPU

2017-06-07 Thread Ming Lei
On Sat, Jun 03, 2017 at 04:04:02PM +0200, Christoph Hellwig wrote: > Currently we only create hctx for online CPUs, which can lead to a lot > of churn due to frequent soft offline / online operations. Instead > allocate one for each present CPU to avoid this and dramatically simplify > the code.

Re: [PATCH 7/8] blk-mq: create hctx for each present CPU

2017-06-04 Thread Sagi Grimberg
Nice cleanup! Reviewed-by: Sagi Grimberg