Dedicated Server hosting - local

[w1z4rd]

@koffiejunkie, have you tried DigitalOceans SSD hosted VPS`s?

 

[koffiejunkie]

@koffiejunkie, have you tried DigitalOceans SSD hosted VPS`s?

No, but i've heard nice things about the quality of their documentation.

RAID10 is hardly a solid approach given what MySQL does to your disks.

Care to elaborate? And yes, I did read the rest of your post.

Granted you have an offsite CDN image store(Great idea for generally large static content and streams--saves on storage and load on your machine | bad idea if the people accessing your site have slow international connections--everyone will just think your site is slow or coded badly).

The point of CDN is that the user gets the content from a local node, *in stead* of your server.

Here is the scenario. Your currently on shared hosting and things are "OK", but its time to move to a more secured and stable setup. koffiejunkie highlighted the 3 key aspects of what is required by your CMS Magento and also what the pitfalls are of the cloud, but let me say this. CPU is hardly an issue provided your content is optimized correctly

The OP asked, and I responded specifically to concerns about hosting Magneto. You comments are quite general and don't leave me with the impression that you know much about Magento at all.

RAM in the cloud and in any cloud should be more than enough on any host, IO, yes this kills and dually noted by koffiejunkie and everyone in the business--however, here is where ZFS comes into play. Get a VPS with enough ram, something like 8 - 12 gigs. Your not looking at using that much at present for your CMS given its on shared hosting. Now you may ask why so much RAM, simply really, ZFS stores all data on RAM before committing to disc.

So does a RAID controller. The difference is a proper raid controller cache is battery backed. In other words, even if your filesystem driver crashes (as the ZOL one still does) or your kernel panics, data not commited to disc yet still gets written reliably. You don't get this when you do everything in a filesystem driver.

Yeah, ZFS is nice, if you run it on Solaris or a recent FreeBSD. But that's make it *better* for all work loads. And stay away from it on Linux.

 

[koeksGHT]

First and only question regarding dedicated hosting:

Why not go VPS?

Motivation:
No hardware or redundancy requirements
No Legacy costs
Easily upgradable

I could go on.

+1

ELitehost local VPS's or DigitalOcean if you want to host cheap but internationally and decent!

@koffiejunkie, have you tried DigitalOceans SSD hosted VPS`s?

They make it so easy I love them!

 

[RNJudas]

No, but i've heard nice things about the quality of their documentation.



Care to elaborate? And yes, I did read the rest of your post.



The point of CDN is that the user gets the content from a local node, *in stead* of your server.



The OP asked, and I responded specifically to concerns about hosting Magneto. You comments are quite general and don't leave me with the impression that you know much about Magento at all.



So does a RAID controller. The difference is a proper raid controller cache is battery backed. In other words, even if your filesystem driver crashes (as the ZOL one still does) or your kernel panics, data not commited to disc yet still gets written reliably. You don't get this when you do everything in a filesystem driver.

Yeah, ZFS is nice, if you run it on Solaris or a recent FreeBSD. But that's make it *better* for all work loads. And stay away from it on Linux.

You make some valid points, I am not looking to argue, simply inform. You are correct when saying I know nothing about hosting magenta, however I know more than a decode of hosting infrastructure. I will answer you as follows:

RAID10:

Theres more than likely a 100% chance this will fail.
RAID10 gives you double the IO and less 50% total store at double the price, but many assume that its the best price to pay for a backup drive, ironically no one notices the the 0% array integrity that any raid outside of 5 and 6 offer. 6 being the lesser of the 2 evils.
When deciding on a raid you need to consider 2 of the most fundamental things. Data Integrity and Cost.
SQL may love double the IO, how much it is depends on the number of disk in the RAID. But the overall performance you get from RAID10 over ZFS is practically minute.

CDN:
Local is perfect. I have no concern with this, in fact if you can get this, then do it!

Specific:
You response to the OP was about magento and it also touched on what the pitfalls and bottlenecks in a VPS scenario is. Hence my direct response on how to avoid these crippling effects in a VPS setup. To overcome resource requirements with the provision for demanding times in mind. Hence my response compensated on those shortcomings for both magento and VPS.

ZFS/RAID:
That is certainly correct, physical raid has a marginal performance gap between software raid, that being said however the overall standing for the software vs hardware raid is practically null and void unless your a windows user, where it would make more sense. *** Giggles fakeraid****. One would simply have to look at the pros and cons to see. Software raid is easily re-storable, you just swap your disks out to another MB and the system takes care of it. With physical your stuck with swapping out to the exact same controller. If your lucky enough to import your array config. Barring ZFS that has a multitude of techniques to ensure data integrity during apparent "failure", applications that require data integrity such as (read databases) ensure that data is flushed to disk. In your statement you say that a hardware RAID overcomes kernel panic... in cases where what? You ever write to a read-only filesystem? Just curuios

The odds of you getting a crash on ZFS vs that of a physical failure on hardware RAID is not even worth laughing at. I have seen more RAID cards die than a ZFS machine having to be rebooted. I still have freenas setups that have outlived a few raid cards.

My overall point was to use what is available and not just compensate but deliver for what could now be a commodity and then be a demand.

 

[koffiejunkie]

Theres more than likely a 100% chance this will fail.
RAID10 gives you double the IO and less 50% total store at double the price, but many assume that its the best price to pay for a backup drive, ironically no one notices the the 0% array integrity that any raid outside of 5 and 6 offer. 6 being the lesser of the 2 evils.

Are you trolling or do you actually believe the stuff you're writing? Going by the above, and assuming the latter, it's difficult to believe you really know what RAID-10 is and/or have any experience with. If you didn't say "less 50%" I could have imagined you got RAID-0 and RAID-10 mixed up.

Where I work we run upwards of 100k servers and storage devices. I don't know the exact number, so lets say 100k to keep it conservative. They all have hardware raid - RAID1, RAID5 or RAID10, depending on the role. In seven years I've been here, we've had two total raid failures. Drive failures happen about once a day (rounded up, it's actually less), which means about 0.3% of the time. We run these drives until they actually die, which is typically well beyond MTBF - three to four times, if not longer.

So how you get to "100% chance this will fail" is a mystery to me.

When deciding on a raid you need to consider 2 of the most fundamental things. Data Integrity and Cost.
SQL may love double the IO, how much it is depends on the number of disk in the RAID. But the overall performance you get from RAID10 over ZFS is practically minute.

Again, you seem to be labelling something as RAID-10 when in fact it isn't. Even on Solaris, ZFS RAIDZ doesn't come close to the performance of hardware RAID-10. Even with a SSD L2ARC, it still doesn't match a good HW raid controller's overall performance (yes, in isolated workloads it will, but in a general web/db server context, no, it won't). I've tested this with every conceivable combination of discs, OS, etc. My results mirror just about every benchmark I've seen before: ZFS is slower.

I get that you're passionate about ZFS, and I don't blame you. It's an excellent filesystem. But please stop talking bunk about hardware RAID. All that fancy features of ZFS comes at a price. That price is performance.

Software raid is easily re-storable, you just swap your disks out to another MB and the system takes care of it. With physical your stuck with swapping out to the exact same controller.

In a hosting environment, having multiple identical spares for any part is par for the course. We routinely move complete arrays from one server to another when there's a need, and this never fails. We can even delete and re-create a RAID set with different parameters without losing data - sleazy but reliable trick to get around certain raid controllers not providing a way to expand the size of a vdisk after swapping out the drives for bigger ones and rebuilding each.

 

[Tinuva]

I do agree, hardware raid will always be faster than ZFS. But one thing hardware raid won't give you that ZFS give you, is protection against silent corruption in data. Now for me with a server at home this will probably rarely ever happen, but you doing 100k servers? I am pretty certain at some point you must have come across that? For me that is the single best reason to use ZFS over hardware raid. Hardware raid however has it's place, like everything else in this world.

 

[RNJudas]

I will endeavour to reply. Since I was not at work yesterday I could not.

Its hard to debate with a man who has 7 years of experience, but to do so will also provide many of us here with insight and experience. However its rather sad to see that instead of asking for clarity or seeing a misconception of something you dont ask for an explanation... Sigh


Raid10: My Perspective.
1 / 1 = RAID1 x2
Then
2 + 2 = Raid 0
= Raid10


Basic construct of 2 drives mirrored and then the 2 vdevs striped.

1, ZFS is not a filesystem, this is a common misunderstanding. Its a volume manager.

2, L2ARC is not the next best thing, its the second level of ARC for when your system runs out of ARC RAM.

3, Hardware RAID at this moment is better but considering what their posting about is shared webhosting looking into dedicated, it is safe to say that we are going the cost effective route.

4, Its worth knowing the point stated by Tinuva about silent data corruption. I have seen this on many occasions and as I mentioned prior you get a slight hint of it in RAID6.

5, Like with anything RAID-like setup, your highest IO peek is the maximum of the slowest spindle in the array. That being said, your write-off, weather its from a ZIL or hardware RAID is bound by that limitation, no ammount of hardware is going to compensate for actual disk performance.

6, Dedupe--Sure there is technology to have dedupe on most things, but nothing like ZFS. Simply given the fact that dedupe is an option at this point one could safely say it is well advised if you take into account that their product changes are minor. On another note, if the data is compressed etc, you could also take into account the less bandwidth to disk and also less disk activity and we all want an idle datastore.

7, Everyone runs till they die, weather its disks or life.

8, ZFS vs hardware RAID maybe slower but considering the difference in performance is not earth shattering, I would have to say my wallet is the happier for it. The gaps between software and hardware RAID is closing, evidently so with processors growing at the rate they do.

9, Hosting grows to fast to be bound by the requirement to maintain and keep around legacy hardware for swapouts.

10, Its a SPOF, Its expensive, your raid card can fail, your RAID volume can fail. I suppose it can be argued that ZFS could be in the boat of failure, but its unlikely, no added hardware no batteries, just get RAM.

11a, Sending data snapshots for added measure of data integrity excluding backups. I see no such thing for RAID.
11b, Restoring snapshots in DR situations.

12, If you have 2 drive failures in the same RAID10 array... Your ****ed... But that was obvious.

I would be curious to know what you had setup and benchmarked in the past, perhaps if you wish to share some details with me I can review. I am always interested in knowing more things

PS: koffiejunkie, you have to show me your sleazy magic trick xD