Multithreaded Read & Write
The multithreaded tests simulate a situation when there are one to four clients accessing the virtual disk at the same time – the clients’ address zones do not overlap. We will discuss diagrams for a request queue of 1 as the most illustrative ones – the speed doesn’t depend much on the number of applications at a request queue of 2 and longer.
The full results can be seen by the following links:
- IOMeter Multithreaded Read results for RAID0
- IOMeter Multithreaded Read results for RAID10
- IOMeter Multithreaded Read results for RAID5
- IOMeter Multithreaded Write results for RAID0
- IOMeter Multithreaded Write results for RAID10
- IOMeter Multithreaded Write results for RAID5
Interestingly, the only HDD with an 8MB buffer in this review, the Samsung HD400LJ, proves to be the best when reading one thread in a RAID0 array. It gives its leadership up to Western Digital’s HDDs as soon as there are more read threads to be processed, though. The WD4000YS then jumps from last to second place, being only inferior to the newer model. The other HDDs are equals until four threads. Samsung’s HDDs are the worst at multithreaded reading, the T133S series models being somewhat slower than the T166S although the latter has higher response time and lower sequential read speed.
It’s the same as with RAID0. The only thing we can note here is the high performance of the Hitachi when reading two threads.
There are no big changes when we switch to RAID5 except that the Samsung T166S is surprisingly slow at reading three threads.
So, the HDDs’ ability to perform multithreaded reading depends but little on the type of RAID. Is it so with multithreaded writing?
Save for the WD4000YS and Samsung T166S, the HDDs all cope well with writing one thread to a RAID0 array. There are changes in the standings at multithreaded writing, though. As opposed to multithreaded reading, both Samsung T133S drives remain in the lead, followed by the WD4000ABYS. Interestingly, the WD4000YS is the slowest in this test irrespective of the number of threads. Take note that the WD4000ABYS gives way to the Samsung T166S when there are four write threads. Samsung’s HDDs are good at multithreaded writing, at least in RAID0 arrays.
Samsung’s T133S series disks are good in RAID10 arrays, too. They are only inferior to the WD4000ABYS, which is the favorite of this test session, but have fluctuations of performance at certain loads. Particularly, the HD401LJ slows down at two threads (and loses to its 8MB-buffer counterpart) while the HD404LJ accelerates suddenly at four threads. The WD4000YS loses this test, just like it did in the RAID0 array.
Samsung’s T133S series drives are in the lead when writing to a RAID5 array. The HD400LJ is ahead at one and three threads while the HD401LJ, at two and four threads. Interestingly, the latter is faster at two threads than at one. The WD4000ABYS and Samsung T166S are quite fast at multithreaded writing, too.