I would discuss here my previous system . I actually downloaded this pre-installed image for Debian 5.0 ( Lenny ) for VMware and started using it. Maybe this OS is corrupt or maybe something else is wrong but other people are using this image fine. I am using Directadmin on this server and also host websites . Anyhow I would explain what happened here :
First of all I had 1GB ram. The ram started increasing/falling by itself and the websites would sometimes act very slow. One day MySQL couldn't allocate much memory and the whole system crashed and I had to restart the machine. Here is how the RAM increased/decreased: ( This just shows some maximum values it touched during 30 seconds ) :
Code:
panel:~# free -m
total used free shared buffers cached
Mem: 1011 999 11 0 0 19
-/+ buffers/cache: 979 32
Swap: 400 103 296
panel:~# free -m
total used free shared buffers cached
Mem: 1011 705 305 0 1 21
-/+ buffers/cache: 683 328
Swap: 400 218 181
panel:~# free -m
total used free shared buffers cached
Mem: 1011 354 657 0 1 22
-/+ buffers/cache: 330 681
Swap: 400 172 227
You can see that the buffers/cache is not being used much but it is real ram and swap which might be causing this crash. I asked Directadmin support to help me. He asked me to get more RAM and optimized the
my.cnf file himself for better performance. I gave 3GB Ram to the server this time and things were a bit better.
The server worked for about 2 days and crashed. This time the error I think was not due to the RAM or related . Here is the screenshot of the error I got:
( Attached )
Anyhow, I restarted it again. Even directadmin support failed to provide me any useful info about it. I thought there could be 2 things that caused the crash.
1. Corrupt Guest OS/ Incompatibility of VMware with Kernel.
2. Issues with Host Server.
The 1st one looked more of an issue to me. So I thought of installing another OS and checking whether both the OS crash at same time. If both OS crashed at same time, the problem would be with the Host machine and if only the previous OS crashed alone, the problem could be with the Guest OS or Kernel incompatibility.
The current usage of my RAM is as follows on that machine :
Code:
panel:~# free -m
total used free shared buffers cached
Mem: 3043 433 2610 0 58 120
-/+ buffers/cache: 254 2789
Swap: 400 32 367
panel:~# top
top - 09:38:15 up 19:10, 3 users, load average: 0.03, 0.08, 0.07
Tasks: 95 total, 1 running, 94 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 3116812k total, 462956k used, 2653856k free, 60196k buffers
Swap: 409616k total, 32888k used, 376728k free, 123848k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 20 0 2036 568 536 S 0.0 0.0 0:03.22 init
2 root 15 -5 0 0 0 S 0.0 0.0 0:00.48 kthreadd
3 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/0
4 root 15 -5 0 0 0 S 0.0 0.0 0:01.32 ksoftirqd/0
5 root RT -5 0 0 0 S 0.0 0.0 0:00.14 watchdog/0
6 root 15 -5 0 0 0 S 0.0 0.0 0:04.82 events/0
7 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khelper
39 root 15 -5 0 0 0 S 0.0 0.0 0:10.32 kblockd/0
41 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kacpid
42 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kacpi_notify
101 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kseriod
139 root 20 0 0 0 0 S 0.0 0.0 0:25.58 pdflush
140 root 15 -5 0 0 0 S 0.0 0.0 0:07.22 kswapd0
141 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 aio/0
657 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ata/0
658 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ata_aux
You can see that even though RAM is free, Swap partition is being used. And cached memory is about 120 MB too. Not sure if it's fine. Swap partition was already made by the guy where I downloaded this OS image from .
Also, I am still waiting for this machine to crash again so I can see if my other machine crashes along with it . Then I can find what issue is causing the error. Maybe then I will shift Directadmin from this machine to the new one.
But what do you think is causing this machine to crash ?
Also explain the RAM usage ?
