# Why high RAM vps?



## peterw (Jul 5, 2013)

My 512MB KVM does have 300 MB of free RAM. My 128MB OpenVZ vps have 20MB of free RAM. Apache with cgi/perl and PostgreSQL don't eat more RAM.

Why do people buy high RAM vps? What can eat more than 512MB of RAM and is not a game server?


----------



## GIANT_CRAB (Jul 5, 2013)

peterw said:


> What can eat more than 512MB of RAM and is not a game server?


MySQL


----------



## vanarp (Jul 5, 2013)

I think many (including me) prefer to have more free RAM to take care of any unexpected spikes in usage. Also, people here do run multiple websites/applications on same VPS.


----------



## tdc-adm (Jul 5, 2013)

For multi sites I think.


----------



## DalComp (Jul 5, 2013)

MySQL and Apache.


----------



## trexos (Jul 5, 2013)

As you said, a good reason are gameservers. I have a 8GB VPS and it's always around 7GB-7,5GB


----------



## rsk (Jul 5, 2013)

MySQL is the main one, and the unusual spikes in website visitors too


----------



## perennate (Jul 5, 2013)

Java


----------



## shawn_ky (Jul 5, 2013)

MySQL, Apache and Tahoe-LAFS.... Backup grid is great, but tends to take up some memory to process everything


----------



## wlanboy (Jul 5, 2013)

I need about 512 MB of RAM to run MongoDB and about 1 GB of RAM for Tomcat.

Both MongoDB and Tomcat are running fine on OpenVZ. But I still prefer KVM with more than 1/2 GB of RAM for a MongoDB server.

So 2 GB of RAM can easily be touched by a vps.

Everything beyond that (2 GB) e.g. Glassfish, JBoss, Oracle needs a dedicated machine.


----------



## jarland (Jul 5, 2013)

Hosting a lot of clients in cPanel will easily make you keep a lot of memory in your back pocket for a rainy day.


----------



## wlanboy (Jul 6, 2013)

jarland said:


> Hosting a lot of ...


True. 500 concurrent users doing comments and your hoster will get a ticket like "may I have some additional RAM again?"


----------



## jcaleb (Jul 6, 2013)

i host some grails apps i write for clients, so they can see it without meeting face to face. 1 grails app on tomcat + mysql around 700mb on kvm,  the 300mb free is leg room for other things.

if i put this into production on small number of users, i think i need at least 2gb ram


----------



## drmike (Jul 6, 2013)

I wish I could shoe horn everything into small RAM.

Not a VPS, but my big projects suffer from: Java, MySQL and memcached.   I can step down the values some.   Currently parked at 8GB+ steady-ish RAM consumption.  Reducing MySQL cache values would drop it maybe 2GB+.   memcached, can shave that too by 2GB+.   Downsized is more slow requests to MySQL for data from disk.


----------



## willie (Jul 6, 2013)

1. Pretty much anything written in java or jvm languages (clojure, scala) needs a lot of ram.

2. Since (at good hosts) there are fewer high-ram vps to a node than with low ram, you tend to get more cpu and i/o performance even if you don't use the ram.

Still though I've never made much use of high-ram vps's (512mb or more).  The extra ram comes in handy for occasional spikes like compiles.  But for ram-intensive processes I've always used dedicated servers so far.  I ran a search engine for a while (few hundred GB of data, tiny compared to web search) that served queries without too high cpu load, but rebuliding the index took 100% cpu for several days.  It's not really feasible to do that with vps's.


----------



## kaniini (Jul 6, 2013)

The CPython VM is pretty memory heavy, even when using WSGI containers like uWSGI.  If you're running multiple uWSGI processes, each one can take 50-100mb RAM easily.

I wonder if pypy is any better on memory usage -- but I suspect that it is probably not.  Perhaps something to look at on a rainy day...

Many of my customers run boards like vpsBoard (i.e. using invision) and this can be memory intensive because IPB likes to make lots of requests per second, and PHP wasn't exactly written with memory efficiency in mind (neither was Python for that matter).


----------



## drmike (Jul 6, 2013)

kaniini said:


> run boards like vpsBoard (i.e. using invision) and this can be memory intensive because IPB likes to make lots of requests per second, and PHP wasn't exactly written with memory efficiency in mind


Just a general question, but has IPB or similar employed query caching or addons for such.    I cache queries like a lunatic.   No way to pull performance and not have to scale into more boxes under load aside from caching.


----------



## Marc M. (Jul 7, 2013)

> Why high RAM vps?



Why not?!


----------



## maounique (Jul 7, 2013)

Marc M. said:


> Why not?!


Exactly. Most people need it for burst times. I usually count that if I am at 512 MB usage in a regular day, i should expect 1 GB at peaks or close.

Since the difference in price between 512 MB and 1 GB is small, it saves me a few eggs on my face and as such is well worth it.

I do not agree you get better cpu if you have a big ram erver on a node with many small. A lot of small threads means CPU is overworked, while a lot of BIG VPSes means there are fewer threads and the cpu spens less time switching, therefore is more available and responsive, even if the taskks themselves are much heavier.


----------

