Topic: physical memory full, any way to clear without reboot?

[splunk]

Is there any way to clear the ram of the server without rebooting it?

http://www.dark7.org/phpsysinfo

[dilligaf]

Hi,
I have the same scenario.
However I have 1GB of physical memory, and I move around from 95-99%.
I have noted reboots clear it, and it starts climbing again from about 20%.
I do not know the answer but thought you would find it helpfull to know even with a GB of ram it happens.

[Kobus]

I had a quick look at your stats and as far as I know you have nothing to worry about. If it starts using the swap file and that fills up thats when you need to look at things again. In your case it is a healthy system as the load averages are all 0 and you are only using 3% swap. Are you experiening any slowness?

hope tis helps.

Kobus

[Garfield]

This is similar to what I have seen on my (former) Linux-based firewall. On that system too almost all the physical memory would "fill up" within the first week after rebooting. But the system ran flawlessly and was only rebooted when the power company had a service disruption (can't afford a UPS). Maybe with SME it's the same ?

[Boris]

Your server's RAM should be used fully. Thats why you've paid for it.
Linux uses all available RAM for caching, and buffering and unless you see extensive use of SWAP memory, don’t worry about it.

[splunk]

Thanks guys.  So, what's resonable for SWAP memory usage?  Should I just not worry about rebooting unless swap is nearly full?

[Brave Dave]

You can clear the swap memory with "swapoff", "swapon" to turn it back on - but - you may kill some tasks off in the process, check your /var/messages after the excersise.

if you are just tipping into the swap memory look to the top command to tell you your biggest users, likely squid, but httpd takes about 8mb for each spare server, and if http is not under duress you can reduce the spare servers. (use the templates of /etc/httpd/conf/httpd.conf)

I don't like to be using swap in large portions for large amounts of time (more than 10-15%), using all your memory is ok/normal but running - say apache - from swap is not optimum.

[hardijs]

I have set up the squid limits quite high so when I see swap memory used at the amount that I do not "like" then I just issue
service squid restart

and that usually clears a bit of less recently used space from squid cache.

Though I think tere is no particular reason to do that.

[paul_sc]

Hi all...I have just been browsing memory usage responses.

I understand this is normal (and by design even) to jump right up to 90% with maybe a 10% swap file.

My curiosity is...what exactly is in this 550MB of cache?? Right now in server/gateway mode i have only 1 pc on the lan side and SME is only running 1 website, mail, clamav and spamassassin

9:34pm  up 1 day,  6:26,  1 user,  load average: 0.00, 0.00, 0.00

141 processes: 139 sleeping, 1 running, 1 zombie, 0 stopped

CPU states:  0.3% user,  0.5% system,  0.0% nice, 99.0% idle

Mem:   772692K av,  720784K used,   51908K free,       0K shrd,   83412K buff

Swap:  265064K av,    8448K used,  256616K free                  553692K cached

TIA

[Reinhold]

Linux Memory Management
http://info-x.co.uk/docview.asp?id=117

Regards
Reinhold

[Reinhold]

FYI

In the following pic you can see memory usage of an
SME that had it's 128MB DRAM upgraded to 256MB in Nov. 2003
(without a real need)
The SME 6.0ß is running without any reboot since then.
All upgrades were added "live" without reboot
incl. some contribs + all security measures  
in fact it's an 6.01 with SA,CLAMAV,SNORT+ACID etc. as of today.

YES the SME is indeed running for a FULL YEAR on close to 100% memory load ... no probs...
what more does it need to prove that there is no need to reboot or think "windows"  
 http://img.photobucket.com/albums/v604/4contribs/sysmon_mem.png

Regards
Reinhold

[paul_sc]

Thanks for the info Reinhold...btw, what are you using to graph the memory usage?


Thanks

[Reinhold]

sysmon + lmsensors
... have a look @ the Ian Wells site wellsi.com


Regards
Reinhold

(stuff I use is based on Shad Lords rpm but updated by hand and modded for each server mainboard)