New here, just checking performance.
I'm new to using Linode, moving a project from Shared Hosting to VPS, and want to make sure that what I am seeing is normal.
I'm on a Linode 2048 with Ubuntu 13.10.
Project consists of Perl Scripts that are creating/updating image files (ImageMagick) every 5 minutes.
CPU Average
Wait: 0.08
User: 35%
System: 4%
After each reboot (from an update for example), I see that memory use as shown in Longview ramps up from around 100 MB to around 1.50 GB (total with cache) slowly over the course of 12+ hours.
Memory Average
Used: 229 MB
Cache: 1.30 GB
Buffers: 166 MB
Swap: 872 KB
From what I understand this is normal, as Linux is allocating memory available to use appropriately.
Does this sound right?
Also, after memory use has stabilized, then I start seeing some sporadic activity (2-3 times an hour) on the Swap Drive, most less then 20 B/s some higher but no more than 60 B/s.
Again, this sounds normal, from what I have read.
I am just a little paranoid, since this is a bit new to me running on a VPS, so I'm just looking to see if this sounds about right.
Thanks!
John
2 Replies
On the linode itself, if you run "free -m" then you'll see what the machine is currently doing
eg on my linode
% free -m
total used free shared buffers cached
Mem: 1024 780 243 0 57 619
-/+ buffers/cache: 102 921
Swap: 256 0 256
Now the "Mem: free" value is memory that's not being used at all. In my case I have 240Mb of memory that's unused. If I cared then I could look to see if I have programs that peak to that usage or maybe I just have too much linode for my needs
The "Mem: cached" and the "buffers/cache free" value (921Mb) means that I have really don't have memory issues. Most of my RAM is used for I/O cache. That's the linux kernel remembering data that's already been read from disk so it doesn't need to hit the disk again.
Finally the "swap" row shows that my machine isn't going anywhere near the swap partition.
In your case you have a tiny tiny amount of swap in use. That could easily be the kernel deciding that some program really isn't likely to need the page of memory that it's claimed, so thrown it out to swap to make everything else even more efficient. 20bytes/s in I/O activity is close to zero, and can be ignored.
You're definitely not short of memory
John