Some advice relating to hosting

[snakes1100]

If he isn't being allocated his share of RAM that the vps is setup to be using, then yes it would be a server issue and not a php issue.

As he has posted numerous times, this doesnt happen when there are 120 users online in his forums, but happens when there are usually only 5, i would agree with mreyes that its a server issue.

[MrEyes]

Originally Posted by snakes1100

Well each OS is different, but you can cat /proc/sys/kernel/shmmax, if that spits out an error saying it dont exist, ls /proc/sys/kernel and see what you have in there.

The default should spit back 33554432 = 32mb

You can try echo'ing in a larger value or change it in sysctl.conf

Im guessing that this may be a issue with the overall server of the vps and the ram not being allocated correctly to your vps, is the host US based or no?

You were correct the command did spit back 3355442

As far as changing this value goes, and I hate to be the noob here, but how do I go about that? and what exactly does it do?

--------------- Added [DATE]1204980409[/DATE] at [TIME]1204980409[/TIME] ---------------

Well last night at 1am (GMT) the server went down again with ~15 guest/users online

Got onto the host tech support guys and it seems that the reason for the outage was DB usage. This is the reply I got from them:

Hello,

Following are the logs showing your database is creating load on main server. Please upgrade to dedicated server asap.

================================================== ==========================
-bash-3.00# mysqladmin pr
+--------+-----------+-----------+-----------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+--------+-----------+-----------+-----------------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| 112190 | eximstats | localhost | eximstats | Sleep | 717 | | |
| 207652 | therevco | localhost | therevco_vbMain | Query | 154 | Sending data | SELECT
post.*, post.username AS postusername, post.ipaddress AS ip, IF(post.visible = 2, 1, 0) AS |
| 207656 | therevco | localhost | therevco_vbMain | Query | 140 | Locked | UPDATE user
SET lastactivity = 1204939692
WHERE userid = 142 |
| 207657 | therevco | localhost | therevco_vbMain | Query | 140 | Locked | SELECT moderator.*, user.username,
IF(user.displaygroupid = 0, user.usergroupid, user.displaygroup |
| 207660 | therevco | localhost | therevco_vbMain | Query | 140 | Locked | UPDATE user
SET lastactivity = 1204939718
WHERE userid = 142 |
| 207664 | therevco | localhost | therevco_vbMain | Query | 136 | Locked | SELECT moderator.*, user.username,
IF(user.displaygroupid = 0, user.usergroupid, user.displaygroup |
| 207665 | therevco | localhost | therevco_vbMain | Query | 138 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207666 | therevco | localhost | therevco_vbMain | Query | 137 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207668 | therevco | localhost | therevco_vbMain | Query | 132 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207669 | therevco | localhost | therevco_vbMain | Query | 126 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207670 | therevco | localhost | therevco_vbMain | Query | 122 | Locked | SELECT moderator.*, user.username,
IF(user.displaygroupid = 0, user.usergroupid, user.displaygroup |
| 207671 | therevco | localhost | therevco_vbMain | Query | 122 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207673 | therevco | localhost | therevco_vbMain | Query | 102 | Locked | SELECT
userfield.*, usertextfield.*, user.*, UNIX_TIMESTAMP(passworddate) AS passworddate,
IF |
| 207674 | therevco | localhost | therevco_vbMain | Query | 26 | Sending data | SELECT *
FROM datastore
WHERE title IN ('','options','bitfields','attachmentcache','forum cache |
| 207675 | therevco | localhost | therevco_vbMain | Query | 26 | Sending data | SELECT *
FROM datastore
WHERE title IN ('','options','bitfields','attachmentcache','forum cache |
| 207676 | therevco | localhost | therevco_vbMain | Query | 26 | Sending data | SELECT *
FROM datastore
WHERE title IN ('','options','bitfields','attachmentcache','forum cache |
| 207677 | therevco | localhost | therevco_vbMain | Query | 19 | Sending data | SELECT *
FROM datastore
WHERE title IN ('','options','bitfields','attachmentcache','forum cache |
| 207678 | therevco | localhost | therevco_vbMain | Query | 8 | Sending data | SELECT *
FROM datastore
WHERE title IN ('','options','bitfields','attachmentcache','forum cache |
| 207679 | root | localhost | | Query | 0 | | show processlist |
| 207680 | root | localhost | | Sleep | 1 | | |
+--------+-----------+-----------+-----------------+---------+------+--------------+---------------------------------------------------------------------------------------

Now to me that is just a list of SQL queries fired at the DB, and doesnt show how/why SQL is loaded. However I do conceed that MySQL was caning the server as at the time I was running "top" and mysqld was obviously extremely busy. Problem is I have no logical explanation.

I know I keep banging on about this but I just can't see how 15 users are generating the same load as 170.

The following is a dump from mysqlreport (http://www.vbulletin.com/forum/showthread.php?t=175177)

MySQL 5.0.45-community uptime 0 10:26:4 Sat Mar 8 12:30:48 2008

__ Key __________________________________________________ _______________
Buffer used 6.54M of 8.00M %Used: 81.76
Current 7.99M %Usage: 99.85
Write hit 41.35%
Read hit 97.75%

__ Questions __________________________________________________ _________
Total 324.62k 8.6/s
DMS 293.14k 7.8/s %Total: 90.30
Com_ 16.67k 0.4/s 5.13
COM_QUIT 14.81k 0.4/s 4.56
Slow (10) 10 0.0/s 0.00 %DMS: 0.00 Log: OFF
DMS 293.14k 7.8/s 90.30
SELECT 213.34k 5.7/s 65.72 72.78
INSERT 38.58k 1.0/s 11.89 13.16
UPDATE 35.87k 1.0/s 11.05 12.24
DELETE 4.43k 0.1/s 1.37 1.51
REPLACE 912 0.0/s 0.28 0.31
Com_ 16.67k 0.4/s 5.13
change_db 14.64k 0.4/s 4.51
optimize 379 0.0/s 0.12
show_create 364 0.0/s 0.11

__ SELECT and Sort __________________________________________________ ___
Scan 59.05k 1.6/s %SELECT: 27.68
Range 41.03k 1.1/s 19.23
Full join 32 0.0/s 0.01
Range check 0 0/s 0.00
Full rng join 0 0/s 0.00
Sort scan 21.22k 0.6/s
Sort range 18.87k 0.5/s
Sort mrg pass 2 0.0/s

__ Table Locks __________________________________________________ _______
Waited 98 0.0/s %Total: 0.02
Immediate 420.02k 11.2/s

__ Tables __________________________________________________ ____________
Open 64 of 64 %Cache: 100.00
Opened 4.74k 0.1/s

__ Connections __________________________________________________ _______
Max used 15 of 200 %Max: 7.50
Total 14.82k 0.4/s

__ Created Temp __________________________________________________ ______
Disk table 148 0.0/s
Table 9.63k 0.3/s Size: 32.0M
File 14 0.0/s

__ Threads __________________________________________________ ___________
Running 1 of 1
Cached 0 of 0 %Hit: 0.01
Created 14.82k 0.4/s
Slow 0 0/s

__ Aborted __________________________________________________ ___________
Clients 8 0.0/s
Connects 0 0/s

__ Bytes __________________________________________________ _____________
Sent 2.97G 79.2k/s
Received 72.78M 1.9k/s

__ InnoDB Buffer Pool __________________________________________________
Usage 576.00k of 8.00M %Used: 7.03
Read hit 97.39%
Pages
Free 476 %Total: 92.97
Data 35 6.84 %Drty: 0.00
Misc 1 0.20
Latched 0 0.00
Reads 690 0.0/s
From file 18 0.0/s 2.61
Ahead Rnd 2 0.0/s
Ahead Sql 0 0/s
Writes 157 0.0/s
Flushes 24 0.0/s
Wait Free 0 0/s

__ InnoDB Lock __________________________________________________ _______
Waits 0 0/s
Current 0
Time acquiring
Total 0 ms
Average 0 ms
Max 0 ms

__ InnoDB Data, Pages, Rows ____________________________________________
Data
Reads 34 0.0/s
Writes 19 0.0/s
fsync 14 0.0/s
Pending
Reads 0
Writes 0
fsync 0

Pages
Created 1 0.0/s
Read 34 0.0/s
Written 24 0.0/s

Rows
Deleted 0 0/s
Inserted 2 0.0/s
Read 2 0.0/s
Updated 0 0/s

This was taken around 10 hours after the server was rebooted early this morning.

--------------- Added [DATE]1204980466[/DATE] at [TIME]1204980466[/TIME] ---------------

This is the header from "top":

top - 12:47:06 up 10:56, 1 user, load average: 0.44, 0.22, 0.20
Tasks: 75 total, 1 running, 74 sleeping, 0 stopped, 0 zombie
Cpu(s): 1.9% us, 0.3% sy, 0.0% ni, 97.5% id, 0.2% wa, 0.0% hi, 0.0% si
Mem: 8146120k total, 7736760k used, 409360k free, 92060k buffers
Swap: 8193108k total, 1240572k used, 6952536k free, 2095432k cached