Hello,

I have been researching this theme and iam from the opinion that is time to go for it.

For what i have researched the Intel X25 E is the best choice for server environment, do you agree? Any other SSD do you advise?

I would like to hear from you.


Regards,

CSPK

Whichever you choose, make sure it is SLC based and not MLC.

SLC = Single-level Cell (X25E)
MLC = Multi-level Cell (X25M, X25V)

You'll find MLC drives typically have higher throughput numbers, but for servers, specifically database and web servers, higher IO and rewrite numbers are more important. This is where SLC shines.

SLC will give you significantly higher IO and rewrite. Rewrite on MLC drives require two operations (if the block has been previously written) and SLC only requires one.

Access times on SLC are a bit better than MLC.

I have a few servers with 15k SAS drives and one server with the X25E in it. There really is no comparison. As long as you are serving relatively small files, or you are hosting a database, the X25E will pull ahead of any SAS setup.

Hello,

I have been researching this theme and iam from the opinion that is time to go for it.

For what i have researched the Intel X25 E is the best choice for server environment, do you agree? Any other SSD do you advise?

Well, it's all to do with performance:cost

For some purposes, the Intel X25M will give a better performance:cost ratio

For example, suppose the main requirement is to handle 2000 smallish - say 20K bytes -random reads a second. Both the X25M and the X25E will handle that. However, Newegg for example sell the 40GB X25M for $130, and the 32GB X25E for $383.

So I'd say the X25Ms are generally better than the X25Es, unless you need the higher write rates the X25Es can achieve.

(And as ever you must be aware of the effect of writing on MLC drive lifetime.)

I agree with you the X25E seems to be the right way to go. Im finding a little bit difficult to find other SSD running SLC technology besides the X25E, do you have any knowledge about other suppliers?

Another question is if the final customer notice the speed difference? I mean in a server dedicated to website hosting.

If the speeds are better the processes will finish faster, so i can suppose the cpu loads and memory usage will get lower giving the chance to host more websites, is this logic?

Another question is if i can set this SSD on any server, since they are 2.5" size and most of servers come with 3.5" bays.

Regards,

CDSPK

If the speeds are better the processes will finish faster, so i can suppose the cpu loads and memory usage will get lower giving the chance to host more websites, is this logic?


The CPU load would not change. Memory usage would fall.

Samsung and OCZ (Vertex EX) do make some SLC. Intel is the biggest consumer supplier so far. If you configure SSD for many hosting companies chances are they will be using the Intel drives.

You can use $10 adapters to fit a 2.5" into a 3.5" bay - they are the same format as notebook drives, only about 3 mm smaller on the top. The Intel drives typically come with adapters.

Customers may not notice the difference in speed depending on how much load the server is under. Are you sure you even need SSDs? If you find your disk queue length is high (ie. processes are waiting for disk access) you may wish to upgrade to something faster.

If you have a small or moderately sized database that is accessing the disk, perhaps more memory will be a cheaper and more effective solution.

I would like to add SSD to present it as an add-on to more demanding customers, customers that want another level of hosting with faster HDD and of course with special prices.

What Vidahost are doing with SSD servers seems to be very interesting, and most likely the way this will go, at least for now as far as I can see. The cost to use SSDs as your main storage is still too high compared to standard drives.

Details here: http://www.vidahost.com/business-plus-hosting/uk-premium-hosting.php

I would like to add SSD to present it as an add-on to more demanding customers, customers that want another level of hosting with faster HDD and of course with special prices.

Hetzner do that; they offer an additional 128GB SSD for $40 a month.

OVH do too; they offer "hybrid" servers, which include a pair of Intel X25M 80GB drives, for an additional $35 a month.

Eventually, I would love to see SSD drives used for primary storage, but I think that will be at least a year or two off (at least for cheap shared hosting). The cost per GB of storage in SSD drives is too high right now to be competitive in the hosting market as a purely SSD storage. MLC SSD drives cost about $3 per GB. SAS drives are running about $1 per GB. SATA drives are about $0.10 to $0.15 per GB. Due to the high cost per GB for SSD drives, I think we will see a lot of hybrid solutions before we see many companies switch to purely SSD drives for storage solutions.

It is definitely time to integrate SSD drives into hybrid storage solutions. These would be solutions where data is stored on SATA and SAS drives, and then SSD drives are used for caching the most frequently used data. We are actually working on some hybrid stuff in house right now down these lines and it looks very promising. One design we are testing has six SSD drives combined with dozens of SATA drives. Using SSD drives to cache the most popular content leads to some notable speed improvements, and the overall cost per GB of storage is still kept pretty low.

The example of Vidahost is the way we are leading to, offer special packages for customers who demand more. Servers with no oversell and SSD drives (with other premium services). I think SSD for now is a good start point to give better service for customers that want to get out from overselled servers and are ready to pay for it.

I voted "not for now", but it depends on your workload...

If you have a relatively small amount of data with a very high performance requirement so that normally you would need to use a number of 15k SAS disks or similar then no doubt I would be happy to use flash for this - the reduction in disk count and improved power consumption alone make it worthwhile.

However the majority of our customers' workloads are not like this - they have a small amount of high-performance data (maybe a few gigabytes of databases, if that) and the rest of their data is only accessed intermittently or wouldn't benefit from the performance of flash. We use 15k SAS disks in a SAN and this gives plenty of performance for the data that needs it whilst also providing a reasonable amount of capacity for the rest of the data - I don't think our customers would want to pay the premium to have all their data on flash.

I like NetApp's PAM approach to flash, which intelligently stores the most demanding data on flash and leaves the rest on SATA disks, but unfortunately this is only available on the higher-end models at the moment.

Gavin

I was actually looking at the SSD benchmarks on tomshardware and was very surprised to see that the x25-m has the same performance as the x25-e. Both the 160gb M and the 32gb E can do 6000 i/o/s in the database benchmark (lots of random writes and random reads), and 12,000 i/o/s in the web server benchmark (mostly random reads). I would have expected the E to pull ahead in the random write benchmark, but they were dead even.

Also, each cell in the E can handle 10x as many write cycles over it's lifetime as the M, however, lets do some math.

First, the E uses a bit more cells per gb because it leaves more of them aside as spare area than the M does. So, 32gb of SLC is probably equivalent to 40gb of MLC, in those regards. As well, you need two cells on SLC to get the same byte count as one cell on MLC. So, 32gb of SLC has the roughly the same number of cells as 80gb of intel MLC. Therefore, the 160gb MLC of intel's has roughly double the number of cells of the similarly priced 32gb SLC.

Now, the SLC can write to each cell 10x as many times over it's lifetime as the MLC. But, it has half as many cells, so the total number of i/o's that can be performed on the drive (in total) is only 5x as many as the MLC.

Now, we have to take into account number of bytes on a given cell. Any write that is large enough to require writing to more than one cell, you're writing to twice as many cells on SLC as on MLC, simply because each cell on the MLC can hold twice as much data. So, for writes that are larger than a single cell, the SLC can only do 2.5 times as many total aggregate i/o requests over it's lifetime as the MLC.

In total then, the SLC only has a small advantage over the MLC (for the intel drives anyway), over it's lifetime, and even then, only for small random writes. Perfect for databases, as others have said.

For more general hosting (thumbnails, images, etc), or for larger databases or more cost sensitive applications, the intel generation 2 160gb x25-m MLC is a fantastic device, and surprisingly, offers nearly identical write performance to the x25-e slc based ssd, for nearly the same price. If you don't need the roughly 2-4x lifetime write cycles, or you need more than 32gb space, it's definitely what you should be using.

All of the above said, SSD are not just the wave of the future, they're rapidly becoming the wave of the now. Those speeds I mentioned, 6000-12000 i/o/s, consider that a SAS drive can do maybe 300-400 i/o/s, and a sata drive can do around 100-150 i/o/s, and you see that, except for mass storage applications or mostly idle filesets, SSD will rapidly become the only viable option, and even today, is a fantastic hosting option in a growing set of circumstances.

Thanks for all your replies, i can see this discussion still divide most of providers, but the bottom end is that Flash drivers will naturally replace HDD as we know them today.

At the present time i think it can be presented has an add value for who wants another level of hosting for their accounts.

Regards,