Hi, I am currently testing running Openstack instance on Cinder volume with libgfapi. This instance is the Windows instance and i found that when running random 4k write workload, the CPU utilization is very high, 90% CPU utilization with about 86% in privileged time. I also tested the workload with volume from NFS and the CPU utilization is only around 5%. For gluster fuse, the CPU utilization is also not as high as 90%, around 30-40%. Is there any reason why is that so? Appreciate on any comments and suggestions. Details. Workload generator: IOMeter Instance: Windows 2008R2 Openstack Host: CentOS 7 qemu-kvm version: qemu-kvm-ev-2.1.2-23.el7.1.x86_64 Workload: 4kb random write, 4 workers with each worker configure to have 4 outstanding IOs Gluster server and client version: 3.7.8 Gluster info Volume Name: g37test Type: Distribute Volume ID: 27947421-111b-4727-bcaf-bafe73debe07 Status: Started Number of Bricks: 1 Transport-type: tcp Bricks: Brick1: 192.168.99.4:/mnt/ssd/g37test Options Reconfigured: performance.readdir-ahead: on nfs.disable: true performance.io-cache: off performance.quick-read: off server.allow-insecure: on storage.owner-uid: 165 storage.owner-gid: 165 Cw -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20160411/121b7ea2/attachment-0003.html>