In our comparison tables you find benchmark values regarding 62 different SSDs. Furthermore we do not comment the benchmark values. The idea and also the goal is to present to you a market overview which helps you choose the right SSD.
We think everybody reading this article can imagine the following scenario: You just bought a hard drive which according the specs sheet should transfer 120 MByte/s reading and writing. In the reviews you read about astonishing 110 MByte/s but after you put the drive into you system it feels much slower. The whole story gets even worse when you start a benchmark which does randomread/write of 4 KByte blocks. There you only get two to three MBytes/s.
Because of this we don't want to publish screenshots of standard programs like HD-Tach, HD-Tune, ... we want our tests to be
reproducible,
accurate
meaningful and
varied ...
... sind.
We
test with activated caches and NCQ (Native Command Queueing) because they're
also activated under daily use. But the data size tested is always at least
twice the amount of the memory. In this there will be no intereference.
We noticed that the measuring error is constantly
within ±2%. Therefore we mention it only here.
Additionally we evaluate the S.M.A.R.T. data
to assess if there are already errors.
The following table give you a brief overview to which points we
turn our centre of attention.
Test
Observations
Sequential Read/Write Tests
Are the values within the
specifications?
Which
influence has the block size?
Which influence has the filesystems block
size?
Random
Read/Write Tests
How severe is the influence on the
theoretically possible (sequential) datarate?
Which
influence has the block size?
Which
influence has the block size on the filesystem?
iozone3
iozone3 is a benchmark suit for storage solutions which natively runs under Linux.
Therefore we are testing
the throughput with different block sizes using the following commands:
It is important to reproduce scenarios of daily usage. Certain parameters need to be variable during the test to make a statement about the product. In our test the parameters are the different block sizes. It defines the size in KBytes which is written/read on the drive during a transaction.
With this method one can test the reading and writing of either small and big files. In a normal personal computer environment you usually don't find many files smaller than 16 KByte. The relative amount of small files is much bigger on a mail or database server. Therefore tests with small block sizes are of interest for database-based applications.
In bigger RAID arrays the hard disk cache is usually disabled and the RAID-Controller takes over the job of caching. Exactly in such setups hard drives need to be very fast when reading or writing small amounts of data. Sequential throughput isn't interesting in this case.
Article in English
Artikel in Deutsch
Article
en français
Articolo in Italiano
