6 Replies Latest reply on Jul 26, 2011 9:10 PM by mistermokkori

    SSD writes are very slow, reads are somewhat slow

    validatorian

      I have the ssdsa2m080g2gc, firmware is 2CV102HD -- I recently ran windows rating thing, and my SSD scored the lowest of any of my compents, a 5.9... so I did some investigating -- turns out, my SSD is slow as molasses... at least, in comparison to other benchmarks I've seen of the same SSD.

       

      Any ideas what the issue is?

       

      AS SSD Benchmark results

      http://i.imgur.com/VP2FR.jpg

       

      CrystalDiskMark results

      http://i.imgur.com/ppwW5.jpg

       

      CrystalDiskInfo results:

      http://i.imgur.com/FDyZi.jpg

        • 1. Re: SSD writes are very slow, reads are somewhat slow
          DuckieHo

          Check AS SSD.... It is telling you that your SATA Mode is in IDE Mode.  You need to enable AHCI in your motherboard BIOS.

           

          Note: You can not just enable AHCI without doing this first: http://support.microsoft.com/kb/922976    

          1 of 1 people found this helpful
          • 2. Re: SSD writes are very slow, reads are somewhat slow
            koitsu

            I'm not sure that's his problem.  I specfically DO NOT use AHCI mode on my system because the Intel RST drivers cause the system to intermittently "stall" for up to 20-30 seconds at a time.  Very weird, but easily reproducible.  So I stick with classic "Enhanced" mode (not Compatibility, so no PATA emulation going on).

             

            It's important to note his SSD is an X25-M 80GB SSD.

             

            The 80GB models of SSDs -- X25-M or 320-series -- really don't perform anywhere near that of the larger capacity models or the 510-series.  If you want some hard data showing this I can provide some (I have 7 screenshots of benchmarks for my 80GB 320-series SSD sitting here ready to go).

             

            Overall I don't see anything wrong with the benchmarks of his SSD given that it's an X25-M.

            • 3. Re: SSD writes are very slow, reads are somewhat slow
              mistermokkori

              the 80gb x25-m g2 has the same performance as the 120gb and 160gb g2's except for slightly lower sequential write speeds.  the 320 and 510 series are a different matter.

               

              validatorian,

              try running the intel ssd toolbox optimizer.  also, enable ahci if you can (you didn't mention your hardware specs).

              • 4. Re: SSD writes are very slow, reads are somewhat slow
                koitsu

                I will repeat myself: AHCI will not solve his problem, and it has nothing to do with his issue.  Please stop advocating AHCI when it won't solve his problem.  I fully understand that it will clear up the red/warning text in AS SSD, but AHCI isn't going to double his write speeds or anything like that.  He's no where near the SATA interface bottleneck speed either (the SSD is, obviously, connected to a SATA300 or SATA600 port -- you can tell from his read benchmarks).

                 

                The root cause of his problem is his lack of free space on the volume -- look very, very closely at his CrystalMark screen shot -- his disk is 90% used (67GB of 74GB used).  CrystalDiskMark 3.x shows disk usage, while 4.x does not (shame on the author!).  I can assure you (download 3.x yourself!) that the numbers indicate how much space is used, not how much space is free.

                 

                Wear levelling is going to result in *extremely* degraded write performance with such little free space available.  Running the Intel SSD Toolbox Optimizer might help increase the performance a little bit, but not drastically.  The only solution is to free up lots of disk space (try freeing up 20-30GB) then running the Optimizer.

                 

                Generally speaking, SSDs perform best when they are left with around 30-40% of the drive unused; the rule of thumb is, the more free space the better.  If you think this is nonsense, read an official white paper on the matter (do not skim it, READ IT) -- it will show you why your performance is sub-par.

                 

                Finally, please keep in mind that the benchmark comparisons you're doing are probably against that of review sites.  Review sites generally take a fresh, never-used-before SSD and benchmark it.  Most review sites DO NOT show you benchmarks of what the drive performs like once it has data on it + has been used for a couple weeks, and absolutely never when it's 90% full.  As such, using review benchmarks for comparison (when data is on your drive) is not accurate.  Estimate a 20-30% deviation in performance as a result.  This applies to SSDs only, not MHDDs (MHDDs do not use wear levelling).  Be extremely wary when reading benchmark reviews.

                1 of 1 people found this helpful
                • 5. Re: SSD writes are very slow, reads are somewhat slow
                  validatorian

                  Thank you all so much for you replies -- I've testing between IDE and AHCI, and AHCI is certainly faster, by about 1.5x in many areas -- the most improvement I got was from running the optimizer, however.

                   

                  Final benchmark:

                  as-ssd-benchmark-ahci-optimized-no-superfetch.jpg

                   

                  Unfortunately, it went down a bit after I rebooted, but it's still considerably faster than what it was before:

                   

                  as-ssd-benchmark-ahci-optimized-no-superfetch-reboot.jpg

                   

                  I'm going to try to free up some space, hopefully enough to make a difference.

                   

                  I really appreciate the help. Thanks again.

                  • 6. Re: SSD writes are very slow, reads are somewhat slow
                    koitsu

                    validatorian wrote:

                     

                    Thank you all so much for you replies -- I've testing between IDE and AHCI, and AHCI is certainly faster, by about 1.5x in many areas -- the most improvement I got was from running the optimizer, however.

                     

                    Switching to AHCI in your case gained you NCQ capability.  You appear to be running Windows 7, where TRIM works regardless if you're using the native Microsoft IDE driver or AHCI driver (truly -- it doesn't matter which, TRIM is an ATA data set management command, and will work on any device that supports TRIM regardless of driver type).  The benchmarks you see in the link I provided in this paragraph are for a completely different model of drive and in a completely different environment.  On an SSD you'll probably see a 10-15% speed gain with NCQ.

                     

                    What probably did you the most benefit was running the Optimizer.  Freeing up space and running the Optimizer again would do you well.  Try to keep your SSD having as much free space as possible -- wear levelling will benefit the most from it, and you'll see the results in performance.  If you want your drive to be restored to factory default condition, you should Secure Erase it (which will be difficult if it's your OS drive :-) ) then re-tune the system as you've already done.