If the data is incompressible you will get a slower sequential transfer speed. At this point it is not clear whether the transfer speed is actually being constrained. Once we see the ATTO results we will have a better idea which direction to go.
@Memrob: No, it’s not the same issue. The other guy has 2 or more SATA 3 ports, some Marvel controllers, some using Intel cotrollers. I have one SATA 3 port using an Intel controller. The fix for him was to switch ports from the Marvel controller to the Intel one. I obvioulsy can’t do that.
@Memrob: No, it’s not the same issue. The other guy has 2 or more SATA 3 ports, some Marvel controllers, some using Intel cotrollers. I have one SATA 3 port using an Intel controller. The fix for him was to switch ports from the Marvel controller to the Intel one. I obvioulsy can’t do that.
I think this is my problem, having 2x sata 3 ports being used. How do Ido the swicth please
@Macsure: This is just the best answer I can give off the top of my head, and only because I’m bored and waiting for a reply to this topic, so plaease don’t take this as scripture or help from the far more experienced admins. That being said…
From what I understand, there is not as of yet a industry wide standardized motherboard color coding format for various SATA type ports, speed or controller type. You’ll need to get the spec sheet on your particular motherboard and make sure you have your SSD/s plugged into the Intel controlled SATA 3 slots.If you have trouble finding the spec sheet the admins here are usually wizards at finding it. Again, this is an outsider’s persepctive, I’m not making any claims as to what they can or can’t or will or won’t do. But it’s probably true if you ask nicely, they’ll help.
Also, if you have more than one harddrive with OS’s you’ll want to make sure the harddrive you want to run Windows is actually doing that. (It’s unliklely that you’ll have more than one OS at any time, but there are certain reasons you might. For example, following the clone of my old harddrive, I had two with an OS.) There are a few ways to do this.
In my case, after the clone of the old harddrive, the only useable SATA 3 slot is in position 3 on my motherboard. (My guess is the architects of my motherboard never intended the SATA 3 slot to be the primary data port position but rather an extra data storage slot.) So I had to switch my SSD to the slower primary (SATA 2) slot and format my old harddrive so that when the computer boots it gets past position 1 (the original harddrive, which is now just a slave sotrage drive) and goes to the only OS which is on the SSD.
Hah, that was it! I had the cable connected to the #3 slot on my motherboard, not the SATA 3 slot. My board simply labels them SATA 1, SATA 2, SATA 3. And because my giant video card blocks 2 of the SATa ports, I couldn’t read the labels. Misleading. Turns out the #3 slot is the only SATA 2 slot on the whole board.
The write speed is very dependant on the wear leveling algorithm.
Therefore it is common that the write speed differes from SSD to SSD. It depends on the total number of bytes written to the device in it’s life-time, how many space is free on the device (or better know to be free by the device), internal fragmentation (no, this means not the fragmentation of the file-system!), …
Hence a difference of 50MB/sec on the maximum write speed is nothing. If the difference is about 200MB/sec we can start discussing about it.
Thant is how all SSDs more or less work. Now you can imagine how important the TRIM command is, otherwise the SSD never knows what block belongs to a file or is already free agaian because of a deleted file.
Hence the general rule is to keep at least 20% free on an SSD, otherwise the write speed can significantly decrease. Additionally this increases the lifetime of the SSD.