From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@linux.intel.com (Keith Busch) Date: Wed, 26 Sep 2018 11:30:19 -0600 Subject: Can not set SMP affinity on kernels above 3.10.0-514 In-Reply-To: References: Message-ID: <20180926173019.GA17405@localhost.localdomain> On Wed, Sep 26, 2018@10:38:12AM -0600, Brian Atkinson wrote: > I am currently receiving the following error whenever I go to adjust > the smp_affinity/smp_affinity_list files for IRQ's associated the > Samsung NVMe SDD PM1725a installed in a Dell PowerEdge R7425 server: > > echo: write error: Input/output error > > I have stopped/disabled irqbalance using the following: > > systemctl stop irqbalance > systemctl disable irqbalance > > However, I still get the Input/output error when I try and echo any > values into either the smp_affinity or smp_affinity_list files. What > is really peculiar about this, is I have no issues updating the values > in these files as long as I am on the stock kernel 3.10.0-514 that > came with CentOS 7.3; however, whenever I get this error on the > following kernels 3.10.0-862.11.6, 4.4.153-1, and 4.18.5-1. Since I am > only experiencing this issue in these newer kernels, I imagine there > is some setting I do not have set that is preventing me from updating > the SMP affinity values for the NVMe SDD's IRQ's. Has anyone else > experienced this issue and possibly know how to correct it? NVMe interrupts are kernel managed, which isn't changeable from user space.