If you have feedback for TechNet Subscriber Support, contact tnsf microsoft. Office Office Exchange Server. Not an IT pro? Learn More. Sign in. United States English. Ask a question. Quick access. Search related threads. Remove From My Forums. Asked by:. There are dedicated controllers to without raid functionality. Yes the write speeds do increase.
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.
This saved me more that two hours because of RAID0 setup. A single SSD will offer good enough performance that I would not recommend it. Two drives in RAID 0 mean if one of them fails you will lose all of your data. TechReport also has this review comparing SSD scaling across a drive family which can help compare the performance delta with larger drives. A large part of the answer to this question will depend on your intended usage. Development, photo editing, gaming, etc can all have different storage access patterns.
Best bet read reviews on the better tech sites. I will say that it is much faster than my personal computer, an M with 2 gb hdd's in a RAID 0 stripe. All of this assume that "with one enough" you mean "Is one SSD not in a stripe enough. And remember Sometimes you must do benchmarks, if you want fast boot read is important, write not so much , if you want to write huge files with random data ensure your benchmark writes at least a few GiB as fast as posible, some SSD have 1 or 2 GiB of RAM inside the SSD for write cache Now answering your question: -If the 'big' one has less than 2x of IOPs than one of 'small' ones, do not buy the 'big' one If you do this, nothing get lost: 1.
If one disk fail, you take out the failed one, put a new one, restore the clone and in a few minutes the system is booting again. Now how to make that boot also fast after one or more disks on a RAID 0 die: 1.
When one disk die, you have that other ones ready to be placed and boot The cost: Have the double of disks Now for data not system in RAID 0 and a zero loose on fail except changes made prior to backup : 1. Remember RAID 0 is great for 'speed' while you use it Think you have a clone of the system on external USB enclosure Think you have all your data on some BackUP more than one copy , loosing data inside the chase is not a problem, just copy back the data from the BackUP after fix what cause the fail replace disks, etc.
Now think you also do not want to wait for such 'copy back' And finally think on ZFS main gains: 1. The short answer is, combined read speed is lower than only one SSD read spead, if you use short stripes for eample 4KiB stripe. Only when i start putting big strip sizes the combined read speed start going higher than single SSD, and i ama talking about 1MiB stripes; gain was about 1. So first, check how good is your SSD in 4KiB with queue depth of one, if it is really good, do not try stripping with small stripe sizes, better at all do not do stripping.
This is necessary to prevent this data from being discarded before it is used. For a server with 8gb ram, 1gb ram use is pretty reasonable. There is a good chance this data will not be flushed before you need it. Meanwhile, you also are having performance issues, and you think a huge readahead may help with this, so you set it to 10MB. However, with a 10MB readahead setting on a server with 10, simultaneous users, readaheads will require GB of ram!
Unless this server GB ram or more, it is certain that most of the data you read from disk will be discarded before a user ever downloads it, making your performance problems dramatically worse. As well this is ram that could otherwise be used for larger TCP buffers, which would speed up users downloads.
For servers with a huge number of connections, these various caches and buffers are a delicate balancing act. We hope this article has helped you learn about an often-misunderstood and important setting for tuning disk performance. With SSDs becoming ever more popular, there are fewer cases where there is a need to tweak these settings. However, for certain websites hosting large files on hard drives, it is still important to optimize these values.
See some of our other articles if you want to know more about similar topics regarding RAID, performance optimization, or server configuration and administration. To get started today, click here to view our dedicated servers , or email us at sales[at]ioflood. We Love Servers. When are the defaults OK? When should the defaults be changed?
What are the optimal settings? Why does stripe size impact performance? To understand this, it helps to visualize what is actually happening in a hard drive. How does an optimized RAID stripe improve performance? Two different ways a KB sized read can occur on a 1MB stripe RAID array In the image above, you can see what happens for a read request depending upon where within a stripe the read occurs.
Can we increase this to huge levels to get even more performance? Modern 8TB drives may perform up to 2x this. But why not increase the readahead and stripe to absurd levels anyway? Do you love servers? About Author gabe. Workloads such as video editing or professional applications involving massive dataset analysis, on the other hand, will eat as much bandwidth as you have to offer. Although SSDs have come down a lot in price over the last few years, they are still many times more expensive on a per-gigabyte basis than mechanical drives.
This makes SSDs unattractive as redundant mass storage. Mechanical drives in purely-redundant or redundant and performance RAID configurations are still very relevant and cost effective for desktop users. However for modern drives, write endurance is far beyond what most users will ever need.
A complete loss of data even when an SSD cannot be written to, is very unlikely. In many ways RAID exists because mechanical drives are prone to failure in the first place. Nonetheless, we can provide some general guidelines:. With a clear picture of where each approach works best, you should have a much better idea which option makes the most functional and economic sense for you.
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