SSD Write Speeds

[Heats10]

Hi there,
I am facing an issue with SSD write speeds.
I am running on Centos 6 with multiple SSD drives.
When I do a hard reboot via KVM, the server is online and the write speeds are perfect. However after a day or two passes, the write speeds are very low almost 5 times lower than normal.
If I do a reboot again, the speeds are back to normal but go low again after 1-2 days.
What exactly might be causing this, any ideas?
Thanks for your suggestions.

 

[powerhouse32]

I'm not familiar with Centos, but here some things to check that could affect write speeds:

1. How much disk space are you using (in %) - if the disks get full (or nearly full), it can affect write speeds.
2. Check for the correct SSD disk setup in Centos - I think this ArchLinux SSD tutorial covers it nicely: https://wiki.archlinux.org/index.php/Solid_State_Drives

Check out the "Trim" section and "Partition Alignment".

3. Check out the firmware on the SSDs. Is it the latest? See the manufacturer's firmware release notes.

Good luck!