On 07/28/2011 02:25 AM, Boris Dolgov wrote:
Hello!
I am using Fedora 14 with kernel and qemu-kvm from Fedora 15:
[root@serv ~]# qemu-kvm --help | head -1
QEMU emulator version 0.14.0 (qemu-kvm-0.14.0), Copyright (c)
2003-2008 Fabrice Bellard
[root@serv ~]# uname -a
Linux serv 2.6.38.8-35.fc15.x86_64 #1 SMP Wed Jul 6 13:58:54 UTC 2011
x86_64 x86_64 x86_64 GNU/Linux
I have a guest with latest CentOS6:
[root@localhost ~]# uname -a
Linux localhost.localdomain 2.6.32-71.29.1.el6.x86_64 #1 SMP Mon Jun
27 19:49:27 BST 2011 x86_64 x86_64 x86_64 GNU/Linux
When I try to load a small MySQL database dump (nearly 10k lines), it
loads a lot of time.
Guest cpu states:
Cpu(s): 0.3%us, 0.6%sy, 0.0%ni, 61.9%id, 37.2%wa, 0.0%hi, 0.0%si, 0.0%st
MySQL Processlist:
mysql> show full processlist;
+----+------+-----------+--------+---------+------+---------------+------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State |
Info |
+----+------+-----------+--------+---------+------+---------------+------------------------------------------------------------+
| 4 | root | localhost | NULL | Query | 0 | NULL |
show full processlist |
| 11 | root | localhost | zabbix | Query | 0 | freeing items |
INSERT INTO applications VALUES (41,10002,'Performance',0) |
Guest top:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1330 mysql 20 0 560m 29m 5900 S 1.3 6.0 0:05.61 mysqld
336 root 20 0 0 0 0 D 0.7 0.0 0:02.39 kdmflush
Looks like you are blocked on disk. What does iostat say about disk
utilization (in both guest and host)?
1367 root 20 0 14928 1212 924 S 0.7 0.2 0:08.42 top
355 root 20 0 0 0 0 D 0.3 0.0 0:03.34
jbd2/dm-0-8
1421 root 20 0 14932 1220 920 R 0.3 0.2 0:00.01 top
Guest is installed inside LVM.
Host cpu states:
Cpu(s): 2.3%us, 4.0%sy, 0.0%ni, 93.1%id, 0.4%wa, 0.0%hi, 0.1%si, 0.0%st
QEMU command:
/usr/bin/qemu-kvm -enable-kvm -name VM7 -nographic -vnc 0.0.0.0:7 -vga
std -m 512 -smp 4 -boot c -pidfile /home/vms/run/7.pid -monitor
unix:/home/vms/run/7.monitor,server,nowait -serial
unix:/home/vms/run/7.serial,server,nowait -net
nic,vlan=0,macaddr=FE:E1:DE:AD:00:07,model=virtio -net
tap,vlan=0,ifname=tap_7_0,script=/home/vms/ifup,downscript=/home/vms/ifdown
-drive media=disk,if=virtio,index=0,file=/dev/vg0/cent6,cache=none,boot=on
I can provide any additional debug information.
What is the reason of this behaviour?
Likely, slow disk flushes.
Try s/cache=none/cache=unsafe/ as an experiment. Does it help?
Try s/cache=none/cache=none,aio=native/. Does it help? This one is
safe, you can keep it if it works.
--
error compiling committee.c: too many arguments to function
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