Let's talk server specks

[JunkyPic]

I'm looking for a server that can hold ~50 people. The point is I don't want to overkill it on the hardware since that would involve more money but I don't want the opposite either. After some searching I've stumbled across some pretty nice offers(Xeon E3-1230, 16 GB DDR3, 120 GB HDD - SSD, 100Mbps Unmetered connection, running on - personal preferance - Ubuntu). This could clearly hold 50+ players at any given time. And the price is fairly decent. However, I want to get a clear view of what I need, not what I want(hell, I'd want a NASA computer if I could get one).

So, let's point out a few facts about Tekkit: Only 1 core of the CPU will be used so there's no point in getting a multiple core CPU with low processing power per core. Tekkit needs as much power per core as it can get. In this case a Core i5 3500, Core i7 3700 or Xeon E3v2 is the best bet when it comes to price/power ratio.

The RAM is equally important. After some trial and error, it seems that every player will need about 200-ish MB RAM(this is pure empirical evidence on my part since there are other factors that influence this, such as plugins, buildings on the map, etc). Assuming that 200 MB is enough, we need 10 GB for 50 players. Let's say 12 so we're nice and comfy. With 16 GB, leaving aside at least 2 GB for the OS, it should do fine.

The HDD. The I/O (Input/output) is also very important. There's no real point in having a good CPU if the HDD bottlenecks. This is where a SSD steps in. The only "problem" is that it will break pretty soon.

There are a lot of software tweks that can be done to minimize lag and strain on the CPU/RAM that I'm not aware of.

So, my questions are:

- What would be your personal opinion on the hardware needed to run a 50+ Tekkit server(be detailed, if possible)?

- What are some software tweaks that I should be aware of?

[Buildbot]

I don't think your stats are right... You don't need 2 gigs of ram for an OS and 10gb for 50 players? You would only need 3-4 at the most. And I don't think a 10k RPM hardrive will bottleneck... Yea SSD's have fast speeds but for the most part it's just overkill nonsense. You aren't writing extreme amounts of data to the server at any given time to justify the need for a SSD.

[Djinnii]

Hardware:

RAM:

It's very doubtful you would need more than 8GB of RAM for any Minecraft server, Tekkit included, because chunks are loaded dynamically, your estimates may be correct if none of your 50 players shared a single loaded chunk, but that's extremely unlikely. The only way your going to use 16GB of RAM is if you use a RAMDisk. If you are building this machine yourself, then sure go for it, but if your paying monthly for it, I'd say the less you can get away with the better.

HDD:

Not really a concern at any point, since the world is only saved to disk on average every 3mins and the majority of it is loaded too and from RAM. The SSD requirement is a marketing gimmick, meant to make you spend money you don't need to. The majority of the files required by the server will be loaded into RAM which is still much faster than any SSD can hope to be. For now, its usually more cost effective to get 16GB of RAM and use a 6-8GB RAMDisk than to use an SSD, it's also from what I've seen, more reliable to go the RAMDisk + regular backup method, than to use an SSD which especially with the earlier generations (SandForce mostly) have a relatively high failure rate. So unless you know the exact brand, make and model of your SSD, it's currently likely to cause you more problems in the long run than it solves.

CPU:

Your mostly correct here, the minecraft server is mostly Single-threaded, so it will only take advantage of 1 core, but most of your plugins aren't. Nor is your OS, A good Dual/Quad core (not a Dual Core with HT) Will perform miles better than any Single Core. Also use a server grade CPU rather than a Desktop one, so that you can use ECC-Buffered RAM, rather than Non-ECC Buffered RAM, the difference is usually negligible, but especially if you start looking into things like RAMDisks, it can cut your failed read/writes right down. (more info: http://en.wikipedia.org/wiki/Registered_memory)

(**HT = Hyper threading - Creating multiple logical cores from a single physical core, usually in the ratio 2:1)

Also when your looking at CPU clock speeds, don't automatically think higher is better, this hasn't been the case for a long time now, you need to pay close attention to what architecture the CPU uses, (if all else fails, just make sure its a recent CPU no more than 2years old)

Host:

If you are still looking at hosts, I would highly recommend CreeperHost They have great prices, amazing customer service, 100% uptime (for me anyway) and practically no limits on what you can or can't do with your server, one of the huge advantages to running a VPS or Dedicated server as opposed to a shell on a shared server. You may well want to look at the Enderman or EnderDragon services.

Software:

OS:

I wouldn't really recommend Ubuntu, since you aren't likely to be spending huge amounts of time playing with the desktop, something like CentOS which is much lighter will perform much better, leaving more resources for your server instance. Ubuntu is great for new Linux users looking for a Desktop replacement, but it's far from an ideal server OS.

Minecraft:

Make sure you use Craftbukkit++ to take advantage of things like item stacking, and other general performance enhancements.

I would also like to point out that if you are looking for someone else to host the machine (ie rent a box from them) that you make sure you are happy with the level of customer service they provide, as you WILL need to use it, and you WILL at some point find yourself stuck in a rut where something has gone wrong and you need someone to go and physically do something to the machine.

[Jelato Foot]

I'm not sure an SSD is as useless as you say Djinnii, the 1.2.5 server is notorious for doing a lot of I/O operations synchronously in the tick thread and yes on it's own may not be a definitive reason to get an SSD, but the majority of plugins use flat file storage or at best sqlite, especially the popular block logging plugins, and I know from experience that they also do all their I/O work in the main thread and most definitely do not keep their storage files loaded in memory.

If you are running a nice vanilla tekkit for some friends then sure a standard HDD will see you good, but the second you start putting plugins in there which most people will consider essential to the running of a medium/large server SSD becomes essential if you want to avoid block placement and break lag under heavy load.

[Djinnii]

I never said it was "useless"... more like Pointless.... You aren't going to get lag from using a HDD, if you absolutely must, then feel free to run your HDD's in RAID like me. (RAID 0 or RAID5 will do fine, no need for a RAID 10 or anything like that. And actually... running multiple SSD's in RAID1 isn't a bad idea. But again... this is going to cost a lot of money and the entire point of this thread is to avoid spending money which doesn't need to be spent. (At least from what I can tell)

I guarantee you that 90% of all lag is perceived lag, rather than actual lag. It's the same as FPS lots of people swear blind that they can tell the difference between 60FPS and 120FPS even though their monitor is only capable of 60FPS being a 60Hz screen.

Also while i'm not a serious programmer... what you are saying doesn't make much sense to me. There's no point a plugin saving "events" with the main thread and not their own or for that matter not keeping actively used files in memory, sounds to me like you did something wrong, because that right there is one of the main jobs of the OS.

(Also for those of you not familiar with the SSD vs HDD argument, the main reason for using a SSD over an HDD is that it has no spin-up or seek time. Making access to multiple files stored in different physical locations on the drive much faster. It's like comparing a USB Flash Drive to a CD-ROM.)

I am in no way saying that getting a good reliable SSD like a Cruical M4 is a bad thing, or that if you have the resources to do it you shouldn't. I am however saying that it's not really a requirement like lots of people seem to think. SSD's are luxury items, there are still plenty of industrial grade servers serving millions of requests per minute still running 5400RPM hard drives.

In any case, 16GB of RAM is still cheaper than a 64GB quality SSD. So a RAMDisk at this stage is still more economical than a SSD.

[Jelato Foot]

Also while i'm not a serious programmer... what you are saying doesn't make much sense to me. There's no point a plugin saving "events" with the main thread and not their own or for that matter not keeping actively used files in memory, sounds to me like you did something wrong, because that right there is one of the main jobs of the OS.

No, it doesn't make sense, which is why it boggles my mind every time I see a plugin with the exact behaviour I described. If plugins were coded correctly then this would never be an issue, but plugins frequently are not coded correctly and are filled with performance holes 9 times out of 10 related to doing work in the main thread which has no business being run in the main thread, most of the time I/O work.

[Djinnii]

No, it doesn't make sense, which is why it boggles my mind every time I see a plugin with the exact behaviour I described. If plugins were coded correctly then this would never be an issue, but plugins frequently are not coded correctly and are filled with performance holes 9 times out of 10 related to doing work in the main thread which has no business being run in the main thread, most of the time I/O work.

Sounds to me like we're arguing about agreeing with each other....

And part of the job of a good server admin, is to run the optimized plugins which do work properly.