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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a requirement to completely disable gluster caching and measure performance on PCIe SSD drive. Below is my vol configuration for disabling performance.<o:p></o:p></p>
<p class="MsoNormal">With these settings, I still see raw SSD speed doesn’t match with the numbers shown by fio with gfapi engine i.,e fio shows speed of 1.5GB/s but raw speed measured at SSD using iostat is around 250-300MB/s, not sure where the rest is coming
from.<o:p></o:p></p>
<p class="MsoNormal">My assumption was if gluster caching is completely disabled, fio speed should be very close to raw SSD speed. Can anyone please guide me in understanding the same?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@vsan-blr4 prashanth]# gluster vol info<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Volume Name: fvol_tun<o:p></o:p></p>
<p class="MsoNormal">Type: Distribute<o:p></o:p></p>
<p class="MsoNormal">Volume ID: 0beec43e-7f75-40e6-8153-075cbd7c3fc8<o:p></o:p></p>
<p class="MsoNormal">Status: Started<o:p></o:p></p>
<p class="MsoNormal">Number of Bricks: 2<o:p></o:p></p>
<p class="MsoNormal">Transport-type: rdma<o:p></o:p></p>
<p class="MsoNormal">Bricks:<o:p></o:p></p>
<p class="MsoNormal">Brick1: 192.168.1.3:/fdata/fbrick1/fvol_tun<o:p></o:p></p>
<p class="MsoNormal">Brick2: 192.168.1.4:/fdata/fbrick1/fvol_tun<o:p></o:p></p>
<p class="MsoNormal">Options Reconfigured:<o:p></o:p></p>
<p class="MsoNormal">performance.cache-size: 32MB<o:p></o:p></p>
<p class="MsoNormal">performance.write-behind-window-size: 524288<o:p></o:p></p>
<p class="MsoNormal">performance.flush-behind: off<o:p></o:p></p>
<p class="MsoNormal">performance.write-behind: off<o:p></o:p></p>
<p class="MsoNormal">performance.io-cache: off<o:p></o:p></p>
<p class="MsoNormal">diagnostics.count-fop-hits: on<o:p></o:p></p>
<p class="MsoNormal">diagnostics.latency-measurement: on<o:p></o:p></p>
<p class="MsoNormal">performance.readdir-ahead: on<o:p></o:p></p>
<p class="MsoNormal">server.allow-insecure: on<o:p></o:p></p>
<p class="MsoNormal">auth.allow: 192.168.1.*<o:p></o:p></p>
<p class="MsoNormal">performance.io-thread-count: 32<o:p></o:p></p>
<p class="MsoNormal">diagnostics.brick-log-level: TRACE<o:p></o:p></p>
<p class="MsoNormal">diagnostics.client-log-level: TRACE<o:p></o:p></p>
<p class="MsoNormal">debug.trace: write-behind<o:p></o:p></p>
<p class="MsoNormal">debug.log-file: yes<o:p></o:p></p>
<p class="MsoNormal">debug.include-ops: yes<o:p></o:p></p>
<p class="MsoNormal">performance.strict-o-direct: on<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-Prashanth<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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