Does a full SSD really have poor performance?

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I've been reading this question about disk issues and am interested in gaoithe's answer for

  1. Does the disk usage really go up when free space declines? If so, why?

I can see why this can happen with a HDD, but can this happen with an SSD?

I have a 128GB Corsair M4 SSD, with only 3GB space left; is this drive performing poorer than if it had 40GB space available?

If so, why?

AStopher

Posted 2014-05-08T12:31:13.187

Reputation: 2 123

Question was closed 2014-05-09T08:05:29.730

What is "disk usage" in that context? Usually it means how much space is left, but the implication here is that it's a measure of the performance of the device. – None – 2014-05-08T12:34:01.903

If TRIM is not available on the SSD or if the operating system doesn't support TRIM (neither of which is the case in your scenario) then having less free disk space could end up causing the SSD to be slower. TRIM will delete from the SSD any deleted files which is a prerequisite before trying to write to that space again. – kobaltz – 2014-05-08T12:35:55.780

Note that "usage" as defined in your linked thread refers to the amount of bandwidth being used for I/O measured in MBps. This can be a good indicator that the disk is not being used by the OS/applications efficiently, but the extent that available bandwidth is saturated, should have nothing to do with the disk itself. Now if you have low bandwidth in use but a high queue count (indicating many pending operations that have yet to be run), then you likely have a hardware problem, but if your bandwidth is saturated, then you probably have a software issue. – Frank Thomas – 2014-05-08T12:43:52.810

@techie007 True. – AStopher – 2014-05-08T18:40:24.690

No answers