

Ask HN: What's necessary re: server RAM? - zimbabwe

I'm signing up for Slicehost right now because I want more freedom with my server. Storage and bandwidth I don't care about much, because I don't do very much transfer-heavy work on my own sites, but how do I judge how effective their RAM offerings are? How much memory does a single hit to a site take? How many concurrent threads can be run with, say, 256MB of RAM versus a full GB? I don't recall ever reading about this before (other than "X site goes down thanks to Digg effect) and I was wondering if anybody had advice about figuring out which would best work.
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bcx
You may want to also take a look at <http://www.linode.com>, they give more
ram, for the same price, and have a pretty slick, albeit not as pretty control
area.

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tdavis
Also, <http://www.chunkhost.com> is, AFAIK, still running a Beta deal where
you can get 512mb chunk for $15/mo, which is pretty sick. Hell, for the Beta
period it costs nothing.

Hello, permanent screen session and homepage!

~~~
listic
For some reason, they only allow beta testers in the U.S. (checked by credit
card)

To think of it, I'm not sure I want to trust my credit card number to new and
unknown company on the internet (they only allow paying by card directly).

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vivekamn
I am running a rails app with 100,000 pages views/month with a 86MB slice(not
at slicehost though) with <2sec response times. The pages are pretty heavy
dynamic pages.

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patio11
Lets see. I have 3 slices, 2 of which are publicly accessible.

512 MB: Apache2 / PHP, serves a dozen websites last time I checked, most
notably a forum that has a few thousand hits a day and my blog, which when it
gets spiky goes up to X0,000 hits in a day.

256 MB (until recently): Bingo Card Creator, which is Nginx => 2x Mongrel.

I bumped the 256 up to 512 (a process that took me above 5 minutes and a
restart) when I started developing the new version, so that I could fit a
staging server on the same box. Currently it has about 6 Rails instances
running on it at any given time (2x Mongrels for the live site, 2x for the
staging, 2x for DelayedJob or consoles). After I release the new version I'm
probably going to put the staging server on another box and reallocate the
saved memory to more instances for the production site.

~~~
listic
Do they give you private IP's to connect non-publicly accessible nodes?
(Linode does) Other way, you'd be using up your traffic limit on this.

How much traffic do your slices use?

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patio11
I have never come anywhere close to my limit. I think the highest I've ever
gotten was a bit over 100 GB a month from the sites, with another 50 GB
through my (private) web proxy (I have a bad Amazon tv episodes habit). My
limit is 500 GB at the moment, so I'm not too worried.

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gojomo
It completely depends on your application/stack. Something with static content
and simple dynamic pages could scream at 256MB, or even less. Something with
other RAM-eating frameworks and code might run best with GB+.

A nice thing with Slicehost is you can start with the smallest, and then if it
seems you need more RAM, can restart the same image on a bigger slice.

You will know if you need more RAM by watching your busy server with 'top'
over time, and among other things, ensuring that it never begins swapping.

Almost any app can benefit from more RAM, especially if you use various levels
of caching effectively (from the automatic linux disk cache through framework-
level fragment- or page- caching to HTTP-server/proxy caching).

So when you're sure things work OK, but then want to make them snappy,
throwing RAM at the problem (with a little engineering to use it wisely) is
usually a good idea.

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zimbabwe
Okay, thanks! So you have experience with Slicehost? Moving up to larger
slices is a painless task?

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radu_floricica
About a half an hour downtime, in my experience. No work needed.

~~~
patio11
It was a matter of minutes for me both times I went from a 256 to 512 slice.

