Adaptec RAID 6805 vs. Intel RS2BL080 (LSI MegaRAID 9260)

W

Wixner

n00b
Joined
Jul 5, 2011
Messages
15
Hello, long-time reader and first-time poster, Wixner here.

I am about to take the step into the world of hardware-raid after several years of software-raid and I'm having a hard time deciding what controller i should go for: In my left hand I'm holding the Adaptec RAID 6805 with it's dualcore PMC-Sierra PM8013 CPU and in my right hand I'm holding the Intel RS2BL080, A rebranded LSI MegaRAID SAS 9260-8i.

The controller will run a Raid5 or Raid6 with atleast six Seagate Barracuda Green 5900 2TB hosting my Microsoft Hyper-V datastore and serve my media-extender with audio and video.
Any suggestion for me? I've tried to read up as much as I could on reviews and benchmarks, but as both controllers seems fairly new the information is pretty scarse.
 
All else being equal, go with Adaptec. It's a long-running company without the rebranding crap you get with Intel stuff.

Besides, the other card has the ports in a weird place. You'd have to go LSI MegaRAID 9261-8i to be an equivalent comparison.
 
I agree that the connectors are placed in a very weird place on the Intel card and I've decided to take a closer look on the Adaptec 6805.

I suppose I should go for the biggest block size as possible as the volume servers 10GB+ files?
 
djstarfox said:
All else being equal, go with Adaptec. It's a long-running company without the rebranding crap you get with Intel stuff.
Click to expand...

By that logic you shouldn't ever use any Intel, Supermicro, Dell or HP cards, since they all are rebranded, possibly to custom firmware (which can be flashed to LSI's default if you want) but are cheaper. Rebranding is the hand of the devil!

djstarfox said:
Besides, the other card has the ports in a weird place. You'd have to go LSI MegaRAID 9261-8i to be an equivalent comparison.
Click to expand...

The place is not weird at all. It's meant to play nice with Intel's RES2SV240, with a very short cable you can easily connect the two cards.

I'd take LSI any day over Adaptec. Adaptec typically uses old Intel IOP controllers, or sometimes newer Marvell or PMC-Sierra. LSI makes their own chips, which are supported out of the box on ANY OS (Solaris too), and they have been around for a long time as well, since 1981, just like Adaptec.

If you want the ports on the back of the card, look for LSI 9261-8i. Or better, pick 9211-8i and do ZFS RAID-Z2 so you get rid of silent data corruption and aren't tied down to any RAID chip either.
 
um yea dont be so hasty fellas LOL

I am currently doing a review of the 9265 and the adaptec 6805 head to head testing with an array of Pliant drives.
Really i cannot divulge too much, but the LSI is in a class its own.
460,000 IOPS with fastpath enabled. you arent going to get that anywhere else. the review should be done by the end of next week if you are patient.
 
Computurd said:
um yea dont be so hasty fellas LOL

I am currently doing a review of the 9265 and the adaptec 6805 head to head testing with an array of Pliant drives.
Really i cannot divulge too much, but the LSI is in a class its own.
460,000 IOPS with fastpath enabled. you arent going to get that anywhere else. the review should be done by the end of next week if you are patient.
Click to expand...

As far as I'm concerned, the LSI 9265 is way ahead of the Adaptec 6805 in terms of hardware with its dual-core LSISAS2208 and its 1GB 1333 DDRIII cache. A more fair comparison would be with the LSI 9260 and its single-core LSISAS2108 and 512MB 800MHz DDRII Cache. Nevertheless, I'm intriguied by your "LSI is in a class its own"-statement.
 
I would go with Intel RS2BL080 (LSI MegaRAID 9260). I have it running perfectly with RES2SV240 giving me 24 ports.
 
rmd3003 said:
I would go with Intel RS2BL080 (LSI MegaRAID 9260). I have it running perfectly with RES2SV240 giving me 24 ports.
Click to expand...

LSI chips are awesome. They work flawlessly with other LSI chips (like expanders), which is what everyone is using.
 
yea. take for instace the areca 4036. nice piece of kit sporting a LSI expander. works beautifully man.
 
I've just received my raid controller and thought i'd share some benchmarks:

Using 256KB Stripe Size
256KB.png


Using 512KB Stripe Size
512KB.png


Using 1024KB Stripe Size
1MB.png


I have not gotten my head around all the options in the raid bios and thought I'd ask you

• Read Policy: Enables the read-ahead feature for the virtual drive. Read Adaptive is the default setting.
— Normal: The controller does not use read-ahead for the current virtual drive.
— Read-ahead: Additional consecutive stripes are read and buffered into cache. This
option will improve performance for sequential reads.
— Adaptive: The controller begins using read-ahead if the two most recent disk
accesses occurred in sequential sectors.

I suppose the Read-ahead option above is the most suitable for a storaga area with large files

• IO Policy: Applies to reads on a specific virtual drive. It does not affect the read-ahead
cache.
— Cached IO: All reads are buffered in cache memory.
— Direct IO: Reads are not buffered in cache memory. Data is transferred to cache and
to the host concurrently. If the same data block is read again, it comes from cache
memory.

Selecting Cached IO above would increase the performance of multiple small reads on the disk but would not increase the performance of single large reads. Am I right?
 
with the LSI controllers if you are using SSD do not use read ahead. ever.
if using HDD use read ahead.

my results with cached I/O were mixed, depends upon workload. for everyday usage i do use cached I/O

do you have fastpath?
 
with the LSI controllers if you are using SSD do not use read ahead. ever.
Click to expand...

Why not use it with a SSD, will it damage it over time?
 
Last edited:
Computurd said:
with the LSI controllers if you are using SSD do not use read ahead. ever.
if using HDD use read ahead.

my results with cached I/O were mixed, depends upon workload. for everyday usage i do use cached I/O

do you have fastpath?
Click to expand...

No, I have no SSD and no Fastpath
 
Got a new set of numbers now after a firmware upgrade and strip- and clustersize change.

1024KB stripesize and 64KB clustersize
Lastest%20ATTO.png


1024KB stripesize and 64KB clustersize
Lastest%20CDM.png
 
@ Wixner:
is this the Intel RS2BL080 wit 6 Seagate 5900 2TB in Raid6?
Whats your write speed when you copy things from an array to an other?
I have the same controller and set up with the intel expander. a Raid six of 8 1TB WD Caviar Blacks and a raid 5 with 4 2TB Caviar blacks by now.
i only get copy speeds of 60MB/sec for one array to an other.
when starting a second transfer it sometimes doubles. but why doesnt 1 copy process take the full speed?
all caches are active.
thanks for your help.
 
Last edited:
Wixner hasn't been active since July 17, when this thread was made. I would be surprised to get an answer from him.
 
jesus my review is 2 weeks late, i just realized this after looking over this again LOL

the adaptec has serious compatibility issues, for those watching....
 
doesnt deal well with expanders, and limited SSD compatibility. Users are having an issue with different SSDs is a big thing. Then the expanders, there is a general lack of support with expanders and "advanced" uses. problem being the uses arent that advanced.
for instance, this expander i am using has two extra expander ports that allows daisy chaining of other enclosures, expanders, OR just plugging in more devices directly on the back end of it. works well with Areca and LSI controllers, but the adaptec will not even see the devices.
their tech support answer is : not supported.
and thats it! most support/etc i have recieved from different manufacturers is usually at least sympathetic LOL. no seriously they try to help, work through it, or put it on an bug fix list.
not adaptec. you get a stock reply.

this is a basic feature inherent of expanders, yet they do not support it. go figure.
So just to use these pliants i have to use a 8088 to 8087 converter, because the true dual port sas cables come only in 8088. included a pic below.
bu
2011-07-2918-56-09052.jpg
 
Last edited:
doncuco said:
@ Wixner:
is this the Intel RS2BL080 wit 6 Seagate 5900 2TB in Raid6?
Whats your write speed when you copy things from an array to an other?
I have the same controller and set up with the intel expander. a Raid six of 8 1TB WD Caviar Blacks and a raid 5 with 4 2TB Caviar blacks by now.
i only get copy speeds of 60MB/sec for one array to an other.
when starting a second transfer it sometimes doubles. but why doesnt 1 copy process take the full speed?
all caches are active.
thanks for your help.
Click to expand...

I am so sorry for the absence but I'm here to give you some numbers:
Raid1: 2xSEAGATE BARRACUDA 7200.12 500GB 7200RPM SATA/600 16MB
Raid5: 6xSEAGATE BARRACUDA GREEN 2TB 5900RPM SATA/600 64MB

1. Copying from my R1 to my R5: Starts at 525MB/S and slowly stabilizes at 160MB/S
2. Copying from my R5 to my R1: Starts at 500MB/S and slowly stabilizes at 130MB/S
 
You must log in or register to reply here.
Back
Top