[Gluster-users] Disabling gluster caching

[Prashanth Kumar N]

Hi,

I have a requirement to completely disable gluster caching and measure performance on PCIe SSD drive.  Below is my vol configuration for disabling performance.
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.
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?


[root at vsan-blr4 prashanth]# gluster vol info

Volume Name: fvol_tun
Type: Distribute
Volume ID: 0beec43e-7f75-40e6-8153-075cbd7c3fc8
Status: Started
Number of Bricks: 2
Transport-type: rdma
Bricks:
Brick1: 192.168.1.3:/fdata/fbrick1/fvol_tun
Brick2: 192.168.1.4:/fdata/fbrick1/fvol_tun
Options Reconfigured:
performance.cache-size: 32MB
performance.write-behind-window-size: 524288
performance.flush-behind: off
performance.write-behind: off
performance.io-cache: off
diagnostics.count-fop-hits: on
diagnostics.latency-measurement: on
performance.readdir-ahead: on
server.allow-insecure: on
auth.allow: 192.168.1.*
performance.io-thread-count: 32
diagnostics.brick-log-level: TRACE
diagnostics.client-log-level: TRACE
debug.trace: write-behind
debug.log-file: yes
debug.include-ops: yes
performance.strict-o-direct: on

-Prashanth

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