Netac N550S Elite 240GB SSD review

 

I/O Performance

There is little point of having an SSD
drive that has blazing sustained reading and writing speeds, if the drive can’t
handle reading and writing of small random files. If you intend to use your new
SSD drive to store and run your operating system, then the drive must be able
to cope with the many small random files that Windows will write to the drive
continually. So I feel it is very important to test how many of these random
files that a drive can handle in one second. I believe that anything over 1,000
I/O’s per second would be enough for most users running a consumer grade
mainstream PC, and should provide a smooth running system. But obviously, the
more I/O’s that a drive can handle, the faster the drive will feel and leave
more headroom for those huge multitasking sessions that users sometimes engage
in.

The things that I will look at are the
total I/O per second and total MB/s.

Partition alignment and sector boundaries

Windows 7 and Vista will automatically
align a partition to 4k boundaries during partition creation, Windows XP won’t.
It is imperative that an SSDs partition is aligned. Windows XP is also
restricted to sector boundaries, while Windows 7 will use 4k boundaries if it
can. The Netac N550S Elite 240GB SSD is 4k boundary aware, and will use these
boundaries if possible. Of course it will also remap LBAs for compatibility
with the sector boundaries so that the drive can be used with Windows XP.

IOMeter allows us to set the sector
boundaries for conducting the tests, and I have therefore set the sector
boundaries at 4K, which means the IOMeter tests are valid for Windows 7 and
Windows Vista users. XP users will not be able to obtain such results.

I will provide a screenshot of the tests on
the review drive for those of you who like to see the actual test result. All
the comparison drive results are represented in the form of graphs.

If any of you would like to see a
screenshot from any IOMeter test on a particular drive, please feel free to request
one, and I’ll post the screenshot in the forum thread.

All the IOMeter tests create a 10GB data
set on the target drive, and each test is run for a duration of 3 minutes.


IOMeter 4K random write test with repeating data.

The first test involves creating continual
4KB random files on the target drive with IOMeter. I use a 4KB file size, as it
is believed that Windows will create and modify many of this size of file
constantly in the background during a typical Windows session. It is said that
most 4K random writes take place at a queue depth of only one.

Queue depth 1

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 1)

Netac N550S Elite 240GB SSD review

The Netac N550S Elite SSD was only able to
reach 69.92MB/Sec which is just okay, but is expected from a TLC drive.

Queue depth 4

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 4)

Netac N550S Elite 240GB SSD review

This time it’s 119.42 MB/sec. Again the
result is okay and demonstrates the limitations of TLC NAND.

Queue depth 32

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 32)

Netac N550S Elite 240GB SSD review

Again we see the limitations of the TLC
NAND, as the Netac N550S Elite SSD was only able to achieve 127.40 MB/sec.

4K random write queue depth profile

For this
test I used various queue depths from 1 – 32 to give you an idea how this SSD
performs at different queue depths. For a normal desktop user, with lightweight
multitasking, the queue depth will rarely rise above 2. For heavy multitasking,
the queue depth is unlikely to rise above a value of 8.

Netac N550S Elite 240GB SSD review

It should be clear that if for some reason
you do a lot of writes, then TLC SSDs are not for you.


IOMeter 4K random read test.

If there are many 4k files created, then
that must also mean that many 4k files need to be read. This test measures 4k
reading performance.

Queue depth 1

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 1)

Netac N550S Elite 240GB SSD review

Read performance in this first test appears
to be good, at 29.49 MB/Sec for the Netac N550S Elite.

Queue depth 4

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 4)

Netac N550S Elite 240GB SSD review

Again the Netac SSD shows an okay result of
82.03 MB/Sec.

Queue depth 32

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD (Queue depth 32)

Netac N550S Elite 240GB SSD review

This time the Netac N550S Elite SSD gave a
good result, and was able to achieve 306.77 MB/Sec.

4K random read queue depth profile.    

This test
shows how the review drive scales with increasing queue depths.

Netac N550S Elite 240GB SSD review

The read performance of the Netac N550S
Elite SSD is good, and if you are a casual user you probably won’t need much
more speed.


IOMeter 512KB write test with repeating data.

Sequential writing performance is also very
important, and in this test I will be measuring the sequential writing
performance of the drive.


Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD – 512K Sequential write with repeating data

Netac N550S Elite 240GB SSD review

The result is simply disappointing. The
Netac N550S Elite was only able to achieve 106.5 MB/Sec in this write test.
This shows how fast the SLC cache runs out causing the drive to slow down
dramatically.


IOMeter 512KB read test.

This test measures 512k sequential reading
performance.

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD – 512K sequential reading test

Netac N550S Elite 240GB SSD review

Read speed shows a different story, as the
Netac N550S Elite delivers a very good performance.


IOMeter Workstation simulation (outstanding I/Os = 64).

When running applications you will find
that there is a mixture of small random files and larger sequential files,
being created and read. Not only that, it isn’t just one file at a time. In
this test I measure a simulated workstation pattern, with a queue depth of 64
(threaded).

Netac N550S Elite 240GB SSD review


Netac N550S Elite 240GB SSD – Workstation simulation

Netac N550S Elite 240GB SSD review

The Netac SSD managed a speed of 234.92MB/Sec
which isn’t the best result that I have seen but it is a good result.

Summary

There are two sides to the story for the
Netac N550S Elite. The one that does not impress is the write speed of the
N550S Elite. The drive is simply slow once the SLC cache runs out, and because
of its size it runs out very quickly. On the other hand if you are casual user,
and you will mainly read from the Netac N550S Elite, the drive is able to show
some good results.

 

Let’s head to the next page for our
power consumption test results…..