Show us your SSD performance 2

Samsung 830 128 GB SSD

Hopalong X said:

If they have System Reserve they often end up at 103424.

1024 is often the offset when there is no System Reserve partition.
As WHS stated above it does not really matter.
The only important thing is the number showing divisible by four (4)?
In both case yours are so both are perfectly fine.

Mike


This is one you previously posted below 32K. It is divisible by 4 so you are good to go.

Unfortunately not true.
My bad!


Read post #324 then #325.> Anvil's Storage Utilities - Page 13

Anvil made the benchmark app you see at the above web site. He is as expert as they get that will actually tell you the truth. Not hem-haw a vague answer and/or avoid your question as some manufacturers.

In his post #325 the SSD needs to have the block aligned. That is why you see many 1024K alignments by W7 if the System Reserve is not installed as mine is set up.

The alignment number should be divisible by or a multiple of "4" but the alignment should be at least 512K. Preferably 1024K or larger.

It is sort of like laying out city streets and then you start the numbering of the houses in the middle of the block instead of at the corner.

If you don't start writing to the proper place on the NAND cell blocks it just messes up the postman.

My Samsung below showing alignment without System Reserve.

Derek, you obviously have the system reserved. If you will use diskpart and select the system reserved partition, you should find an offset of 1024. If you check the partition of your "C" drive, you should find an offset of 101. 1024 X 101 = 103424, which is how it came up with that number. The system partition is aligned at 1024. If you had no system partition, the whole drive would be 1024.

But I raised the issue earlier
Show us your SSD performance 2
Real world applications don't typically do 4K aligned read/writes. So is some of the alignment issues and benchmarking unrealistic?
Sure aligned drives will score higher in Benchmarks because the Benchmarks do aligned Read/writes.
Have I got things wrong here?

mjf, I don't know if you are right or wrong. I have always been under the impression that any writes to an SSD are controlled by the SSD controller. It has been my understanding that the controller and firmware decide how and where the data is written. The same as an erase, the firmware tells Windows which blocks are erasable. That has just always been my impression. I may be wrong.

Derek, Correct me if I am wrong. According to that article the alignment must be divisible by 1Mb or 2MB. If your alignment is 103424kb, that is, according to my math, 101MB, so would be divisible by 1MB. I never excelled at math, but I thought any number was divisible by 1, but maybe not 1MB. Not to worry, Mike will be along to set us straight.

Derek, If I understand the post Mike was referring to, you are correct. I think it was saying just divisible by 4 isn't enough, it need to be larger than 512KB preferably 1024kb. And I agree, mjf has a good question. I just wonder if anyone can definitively answer it. But I do believe the SSD controller decides what is written where. At least I hope so. Otherwise, alignment would mean nothing except in benchmarks.

essenbe said:

But I do believe the SSD controller decides what is written where. At least I hope so. Otherwise, alignment would mean nothing except in benchmarks.

You believe correctly :)