Does RAID 0 (striping) with two SSD hard disk make any sense?
I have a notebook (Dell M6500, 16GB Ram, I7-940M) with RAID controller (hardware raid controller). At the moment I have two SATA HDDs in RAID 0 (stripe) for best performance.
I want to buy SSDs (Samsung 840 pro).
Does RAID 0 (striping) with two SSD disk make any sense or just one disk enough?
So 1 ssd 512GB (no raid) or 2 ssd 256GB (raid 0 stripe)?
You need to read the question properly.
He is asking about RAID0 STRIPE, not RAID1 MIRROR.
My answer: YES you will have a significant speed improvement.
ref: http://staff.science.uva.nl/~delaat/rp/2009-2010/p30/presentation.pdf
Speed: My workstations do run Linux Mint using software raid (mdadm) and I do run 4 drives in a stripe having XFS as filesystem. Once you sit on such workstation, You do not want to turn back to the old days with ONE platter drive.
Backup your workstation daily with incremental backup, weekly a full backup just in case one SSD crashes.
Your speed is great but if ONE ssd does crash You loose a lot of data. So You are warned.
Backup and use cloud to store additionally files.
Storage: My NAS is purely running FreeBSD ZFS ZRAID2 for storage with 2+4 drives of 3TB, so I have 12TB and 2 drives of 3TB do provide redundancy, so I can loose 2 drives at a time without loosing data. My NAS does run on regular drives.
ZFS is currently the best filesystem for disks, for sure for storage. You can look for FreeBSD or a dedicated NAS software solution such as FreeNAS, ZFSguru, NexentaStor ... I did choose ZFSguru because I do like to teweak the FreeBSD system. I use iSCSI and SMB/NFS shares on it.
Servers:
My favorite is to use platters for ZFS and use SSD for ZIL in ZFS. But it is dark art.
NOTE 1:
Try to avoid hardware raids, in case of failure You need to have the same hardware again. Do not use the cheap raid controllers on the customer motherboards. Try to use software raid supported by the OS, just for sake of recovery, as the OS has more ways to deal with raid as most crappy raid software in those hardware controllers.
NOTE 2:
When using ZFS avoid at all costs hardware raid controllers. Look for motherboards with enough SATA ports to connect Your drives. There are dedicated controllers to without raid functionality.
Setup the raid using ZFS
NOTE 3:
SSDs no longer scale after 4 disks HDDs continue to scale after 5 disks
NOTE 4:
There are different types of SSD
You have SSD SLC and MLC. The first are the most expensive but the fastest and the best for heavy read/write operations.
Yes the write speeds do increase. I am running a raid 0 on 4 SSDs at 30GB each my write speed pushes 600MbPS I will be upgrading soon to 2x 256 SATA3 SSD Raid 0 drives, with only one disk it runs at 300MbPS so it is up to you, it also depends on the SATA rating if you have 2 SATA 3 SSDs you can write up too 900MbPS but that requires a Raid 0 set up as well. So it is completely up to you if you would rather have performance. Yes it is faster, and yes you will lose all the data, but if its just for gaming you can rebuild it in less than a day. Also if your options were to either get 2x 256GB SSDs or 1x 512 SSD i would go with the 2x 256 SSD, for much faster writing speeds.
Here is the test I have done. you can decide your self looking at the result.
Enviroment
- CPU: Intel Xenon CPU E5-2650 v3 @ 2.30GHz (core 10, Logical Processor 20)
- RAM: 32GB
- File : sample.rar (13.5 GB size)
- Windows 10
Test
My workstation includes.
- 2x 1TB SSDs setup as a RAID0 Drive
- 1 TB Hard drive
- Used Cygwin terminal,
cpandtimecommands - If you are not families with
timecommand uses 'real time' to compare each case
Here is the file copy time for each situation
RAID0 to RAID0
real 0m17.089s
user 0m0.140s
sys 0m10.686s
RAID0 to HDD
real 1m25.302s
user 0m0.437s
sys 0m21.078s
HDD to HDD
real 1m17.935s
user 0m0.265s
sys 0m14.921s
HDD to SSD
real 1m29.908s
user 0m0.359s
sys 0m13.281s
Note: In my workstation I uses this RAIDO drive to Compile 150GB large C++/C# project. This saved me more that two hours because of RAID0 setup. If you need how to setup the RAID0, have a look to the blog post I have wrote http://codeketchup.blogspot.sg/2016/03/how-to-setup-raid-0-with-ssd.html