Is it possible to dump the current memory allocated for a process (by PID) to a file? Or read it somehow?
I am running top to monitor my server performance and 2 of my java processes show virtual memory of up to 800MB-1GB. Is that a bad thing?
What does virtual memory mean?
And oh btw, I have swap of 1GB and it shows 0% used. So I am confused.
Java process = 1 Tomcat server + my own java daemon Server = Ubuntu 9.10 (karmic)
Why does my server show
total used free shared buffers cached
Mem: 12286456 11715372 571084 0 81912 6545228
-/+ buffers/cache: 5088232 7198224
Swap: 24571408 54528 24516880
I have no idea on calculating the memory in linux. I think it says that 5088232 is used where as 7198224 is free, meaning it is actually consuming 5GB of RAM?
I'm running Windows 7 on a dual core, x64 AMD with 8 GB RAM.
Do I even need a page file?
Will removing it help or hurt performance?
Would it make a difference if this is a server or a desktop?
Does Windows 7 vs. Windows 2008 make a difference with a page file?
This is an old question that I've seen from time to time. My understanding of it is rather limited (having read about the differences a long time ago, but the factoid(s) involved never really stuck).
As I understand it,
Buffers
Are used by programs with active I/O operations, i.e. data waiting to be written to disk
Cache
Is the result of completed I/O operations, i.e. buffers that have been flushed or data read from disk to satisfy a request.
Can I get a clear explanation for posterity?