High load

[ARPLink]

Hi,

In the last 24 hours, my server started to have an increased load time. Normally, it will stay around 3-4, but not it stays between 15-20.

Here is a top and free output:

Tasks: 271 total, 1 running, 270 sleeping, 0 stopped, 0 zombie
Cpu(s): 14.7%us, 4.9%sy, 0.0%ni, 75.6%id, 3.9%wa, 0.0%hi, 0.8%si, 0.2%st
Mem: 7340032k total, 6894408k used, 445624k free, 174848k buffers
Swap: 4194296k total, 2736k used, 4191560k free, 4982420k cached


root@s1 [/home/]# free -m
total used free shared buffers cached
Mem: 7168 6775 392 0 154 4931
-/+ buffers/cache: 1690 5477
Swap: 4095 2 4093


My configuration is:
Xeon Quad core
7 Gb RAM
CloudLinux+cPanel

Also, I would like to mention that EAProc WaitQ is always 0 for every site. Do you have any suggestions?

Here are the console settings for LiteSpeed:

Connection:

Max Connections=150
Max SSL Connections=100
Connection Timeout (secs)=300
Max Keep-Alive Requests=50
Smart Keep-Alive=Yes
Keep-Alive Timeout (secs)=2
Send Buffer Size (bytes)=0
Receive Buffer Size (bytes)=0
I/O Event Dispatcher=epoll (Linux 2.6 kernel)
Max Cached Small File Size (bytes)=8k
Total Small File Cache Size (bytes)=50M
Max MMAP File Size (bytes)=2M
Total MMAP Cache Size (bytes)=200M
Use sendfile()=Yes
Use Asynchronized disk I/O (AIO)=Keep File Mapped (64 bit OS)
AIO Block Size=8M
No I-Node in ETag=Not Set
SSL Hardware Accelerator=(built-in) OpenSSL internal engine

Request/Response
	   
Max Request URL Length (bytes)=8K
Max Request Header Size (bytes)=16380
Max Request Body Size (bytes)=500M
Max Dynamic Response Header Size (bytes)=8K
Max Dynamic Response Body Size (bytes)=500M

GZIP Compression	  

Enable Compression=Yes
Enable Dynamic Compression=Yes
Compression Level (Dynamic Content)=4
Compressible Types=text/*, application/x-javascript, application/xml,
Auto Update Static=Yes
Static GZIP Cache Directory=Not Set
Compression Level (Static File)=4
Max Static File Size (bytes)=1M
Min Static File Size (bytes)=32K

Per Client Throttling   
  
Static Requests/second	=20
Dynamic Requests/second=5
Outbound Bandwidth (bytes/sec)=0
Inbound Bandwidth (bytes/sec)=0
Connection Soft Limit=10
Connection Hard Limit=50
Block Bad Request=Yes
Grace Period (sec)=2
Banned Period (sec)=300

External Application Resource
	   
CGI Daemon Socket=Not Set
Max CGI Instances=40
Minimum UID=11
Minimum GID=10
Force GID=Not Set
Priority=0
CPU Soft Limit (sec)=300
CPU Hard Limit (sec)=600
Memory Soft Limit (bytes)=100M
Memory Hard Limit (bytes)=150M
Process Soft Limit=10
Process Hard Limit=15

LiteSpeed API App Definition
	   
Name=lsphp5
Address=uds://tmp/lshttpd/lsphp5.sock
Notes	=Not Set
Max Connections=50
Environment=PHP_LSAPI_MAX_REQUESTS=150  PHP_LSAPI_CHILDREN=50
Initial Request Timeout (secs)=60
Retry Timeout (secs)=0
Persistent Connection=No
Connection Keepalive Timeout=2
Response Buffering=No
Auto Start=Yes
Command=$SERVER_ROOT/fcgi-bin/lsphp5
Back Log=100
Instances=1
suEXEC User=Not Set
suEXEC Group=Not Set
Run On Start Up=No
Max Idle Time=2
Priority=-1
Memory Soft Limit (bytes)=500M
Memory Hard Limit (bytes)=600M
Process Soft Limit=10
Process Hard Limit=15

[NiteWave]

Max Connections=150

is too low. the default is 2000.
the reason to change the default value?

check if any cloudliunx limit set too low ?

please paste a real-time stats screenshot, it'll help to identify the bottleneck, where the problem is, etc.

[ARPLink]

Hi,

Here's an output of real-time status:



I modified Max Conn accordind to your indication, installed CageFS(from CloudLinux) and the load dropped, but looking at the image, it seems to be large for only 37 requests

[NiteWave]

yes, "Http Used" is 37 in this snapshot.
but in case ddos time for example, the "Http Used" may increase to 1000+ in a few seconds. in this case, the web server may not work properly and cause the load high for a long time. Leaving much buffer as possible often is a good practice.

[webizen]

for quad core server, 4-5 load avg isn't a big deal.

[ARPLink]

NiteWave,

Any suggestions on buffer size in MB based on the existing RAM memory(it hat 7 Gb allocated).

Webizen,

I'm aware that that's not a big load. As I said in the first post, when I asked, the load was at a minimum of 15. My issue is that it still looks to be a slightly big load considering the low number of requests that LiteSpeed has(especially considering that MySQL is on a dedicated server)

[NiteWave]

Send Buffer Size (bytes)=0
Receive Buffer Size (bytes)=0

is ok. 0 means default OS buffer size.