computers for renderfarm

[meanadam]

A little late for this conversation, but here is my experience:

Dual is better - almost 2x. With new HT (2.4 xeon or better) - you get 2 buckets per cpu. Dual machines are typically less than 2 separate machines - so you are getting almost 2x the render power for less than 2x the cost. Not to mention the space, maintenance requirements, and overhead costs associated with 1/2 the machines.

Ram will make the biggest difference - Max out whatever you can get. It is also better to get 1 gb of DDR2 than 2 gb of DDR whatever. Yes, Xeons are faster (bigger cashe). Yes, heat is an issue - get at least 2u boxes and put fans in front and back for flow.

We run dual 2.4 xeons with 2gb of Ram in 4U cases. These machines are about 8 months old.

Now, who wants to talk about HD arrays and stripe configurations?

a

PS - just saw this post - http://www.chaoticdimension.com/foru...ic.php?t=10391
There is your anwser right there.

[CCS]

I agree with you. For me though, money was an issue. I had to decide whether to get a good speed increase now, or a better speed increase later when I can afford it. I decided for now at least to buy what I can afford when I can afford it.

For a larger company with an adequate budget, go for the duals!

[tammo]

the last benchmarks on this board have shown that the dual machines are only 40 % faster the the single processors.

two single processor pcs are much faster and cheaper then a dual.

for a new renderfarm i would get small barebones and a gigabit network.

[dennis]

the last benchmarks on this board have shown that the dual machines are only 40 % faster the the single processors.

two single processor pcs are much faster and cheaper then a dual.

for a new renderfarm i would get small barebones and a gigabit network.

yes they are cheaper but not necessarily 40% cheaper.
Last time we were shopping we got duals we liked much cheaper than good 2xP4 pc's ( though im sure its possible the otherway around too, just worth having in mind )

[percydaman]

thats what ive been saying... sure the duals aren't as fast as 2 single processor computers... but im sure that if you created an equation that figured out render speed per dollar, the duals would come out on top.

[super gnu]

weve got a bit of a mix here too. just purchased a load of dual 3gig 1u rackmounts, since we are running out of space in our office, and from past experience whenever we use standard pc's in our 'farm, they always get nicked from the render room and used for new people starting/replacing bust machines. as a result our renderfarm is always shrinking damn architects should keep their hands off!

anyway from my experience, you can indeed get good value for money on single processor machines, but be wary of the ultra cheap end of the market... we got some single 2.4 p4's from compaq a few years back, they were about £500 each (REALLY cheap at the time!) and worked ok, trouble is they have no free ram slots, (1 gig installed) and the psu is really weedy, had no end of problems with them over the past few months (out of warranty).

once you start spending on decent components that will last, the price difference between single and dual starts to shrink (since if the components cost more, and you are having to buy twice as many of them...) also if you want 2 gig of ram (wouldnt go for less..) and you want dual channel (really worth it) then thats about £300 quid of ram. so the less times u have to buy it the better.


also depends if you ever plan on using them for anything other than rendering (wouldnt advise it if possible, almost impossible to keep a functioning renderfarm when u have 30 people all fiddling with the damn machines.)

lol basically im saying they both have advantages.

if u are tight on space, or need good performance for stills, or find a good deal (we found our dual 3.0 em64t xeon rackmounts for £1100, and they overclock nice (stable for 2 weeks and counting at 3.4 each.) then go dual.
(id rather have less, faster machines than loads of crap ones.)


if you have a big room, lots of money for electricity and dont mind setting up and servicing twice as many machines, then single is the way to go.

you may save a few hundred quid, but there isnt a lot in it ive found.


to the person who says 1 gb ddr2 is better than 2gb ddr... why exactly??

ddr2 is simply ddr ram that uses less voltage and will allow higher clock speeds. it offers virtually no benefit over ddr now, and in some cases is actually worse (latency) and to say that its better to have half the ram is frankly a bit bonkers!

[percydaman]

good post super gnu. agree wholeheartedly...

[meanadam]

DDR2 is better than DDR if you are having bottlenecks due to ram speed. If you are running pc2700 400 mhz ram on a 800 buss – ½ as much 5400 DDR2 675mhz is gonna be a huge step up… Same reason xeons with 1mb cache are better than p4s with only 512 or 256 - or is that bonkers too?

The current issues with computing are - hardware as outpaced software, and processors have gone faster than the rest of the machine. When your cpu(s) are going so fast that the ram can't keep up, and you are using the HD for cache - it really doesn't matter what 3.X chips you have or DDRs. All steps of the process must be optimized – from bus speed to even HD RPM.

I did do the calculations last year.... whish I still had them. I have also forgotten - but it was very evident the cost per gig was much higher with older slower machines I think I was comparing times of 20mins vs 4 or 5 mins. I dropped all old dual p3 machines for ½ as many new dual xeons. Comparing matched machines might only be 40% gain, but once all other components are up to speed and the cost of 40% gain is only a 2nd chip – that is a huge savings.

[super gnu]

i agree that ddr2 is faster, and will get more so in the future, but to say its better to have 1 gig ddr2 over 2 gig ddr is going rather too far id say!

amount of ram makes so much more difference to rendering than the few percent speed increase u get from ddr2's higher clock speed. and besides, pc2700 is ancient, my machine at home is an fx55 with pc4400 ddr (550 mhz) and goes like a rocket, memory bandwith only a few dozen megabytes slower than the best ddr2 available, and latency is far better.

within a year or two there will be no contest, ddr will be dead and buried, but then have u seen xdr ram? to be used with the cell processor in ps3, now that's fast! -ddr2 will probably look old by then too.

the new p4 chips all have 2mb cache (released on sunday), 1 mb is standard.
its been a while since they had 512 kb although u can still buy them if u look.
and when they did, the xeons did too..

anyway, enough post hijacking, back to the discussion at hand!

[paulison]

2Gb of ram can still cost more than the actual processor so although It is a good idea to get 2Gb, think hard if you actually need more than 1Gb on your renderfarm.

Consider than these computers wont be running anything else, and use less ram through backburner with the VFB turned off (i think). Do your scenes really need 2gb? Ive worked on a few multistory jobs recently that stay under 1Gb memory usage. Im fairly certain the render slaves with DR also use much less ram

1Gb single processor machines are good and cheap. For huge developments with lots of trees and displacement, go for 2Gb...but if you get those, you can afford it :P

[percydaman]

at work 2gb was never not an option. forget a multistory...try several city blocks, all multistory...

[super gnu]

yeah we still have a few old machines with 1gb, but id never consider that as enough on a new machine now, id say every job weve done in the last year has pushed it even in 2gb, and even if its not a huge multistorey cityblock. im doing a small courtyard on the back of a large developement at the moment, huge project, but the courtyard is a seperate model, and despite its small size, it has glossy refs, and 5 treestorm trees, area shadows and nice aa for the animation. it is impossible to render in one go even with 2gb, i have to render 3 of the trees in a seperate pass, and even then the ram usage is close to the limit.

point is, as the processors get faster, you want to use all these fancy effects, since it makes your work look nicer. u try doing any serious displacement with 1gb ram..

its true that the rendernodes use less ram than a full copy of max would, but if your in the business of owning a renderfarm, youre probably at the stage that requires a decent amount of ram... our 1gb machines will still render, but you should see the slowdown when they start swapping to their (cheap, like the machines) hard drives.

[trixian]

As a small digression, does max (not including a loaded scene) use any less ram in backburner mode, or is it the same? One would think Discreet should write a rendrer node version of max that doesn't have anything in it that lets you interact. Surely that could help with ram consumption on slaves. Then again, if or when vray goes stand-alone, this wouldn't be an issue.

[percydaman]

max does use considerable less ram when when rendering in backburner. Dont ask me why, its has all the same windows up when rendering that my workstation does.

[Dynedain]

As a small digression, does max (not including a loaded scene) use any less ram in backburner mode, or is it the same? One would think Discreet should write a rendrer node version of max that doesn't have anything in it that lets you interact. Surely that could help with ram consumption on slaves. Then again, if or when vray goes stand-alone, this wouldn't be an issue.

If you run backburner as a service on the rendernode, and set it to its own user (instead of interact with the desktop) and make sure you dont have the frame buffer turned on, max will consume significantly less ram when netrendering. The difference will be about the same for all jobs since its the memory saved by not loading up all the UI.