CentOS was updated and now it very very slow. (CentOS Linux release 7.5.1804 / 3.10.0-862.14.4.el7.x86_64)
VM system: 2012 R2 Hyper V / i3-2120 / 16 GB /HDD WD5000AAKX-001CA 2Tb
I make some tests:
[root@bitrixcrm ~]# dd if=/dev/zero of=tempfile bs=1M count=1024 oflag=direct
1073741824 bytes (1.1 GB) copied, 38.7399 s, 27.7 MB/s
[root@bitrixcrm ~]# dd if=tempfile of=/dev/null bs=1M count=1024 iflag=direct
1073741824 bytes (1.1 GB) copied, 10.8025 s, 99.4 MB/s
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If I add «nobarrier» to /etc/fstab
LABEL=bxRoot / ext4 defaults,noatime,nobarrier 1 1
LABEL=bxBoot /boot ext4 defaults,nobarrier 1 2
LABEL=bxSwap swap swap defaults,nobarrier 0 0
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Tests result:
[root@bitrixcrm ~]# dd if=/dev/zero of=tempfile bs=1M count=1024 oflag=direct
1073741824 bytes (1.1 GB) copied, 15.0595 s, 71.3 MB/s
[root@bitrixcrm ~]# dd if=tempfile of=/dev/null bs=1M count=1024 iflag=direct
1073741824 bytes (1.1 GB) copied, 10.8574 s, 98.9 MB/s
Then I make clean VM system on the same server and run test:
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[root@localhost ~]# dd if=/dev/zero of=tempfile bs=1M count=1024 oflag=direct
1073741824 bytes (1.1 GB) copied, 1.17313 s, 915 MB/s
[root@localhost ~]# dd if=tempfile of=/dev/null bs=1M count=1024 iflag=direct
1073741824 bytes (1.1 GB) copied, 0.918117 s, 1.2 GB/s
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Add Info:
[root@bitrixcrm ~]# sdparm /dev/sda
/dev/sda: Msft Virtual Disk 1.0
mode sense (10): transport: Host_status=0x07 [DID_ERROR]
Driver_status=0x00 [DRIVER_OK, SUGGEST_OK]
mode sense (10): transport: Host_status=0x07 [DID_ERROR]
Driver_status=0x00 [DRIVER_OK, SUGGEST_OK]
Caching (SBC) mode page:
WCE 1 [cha: n, def: 1]
RCD 0 [cha: n, def: 0]
mode sense (10): transport: Host_status=0x07 [DID_ERROR]
Driver_status=0x00 [DRIVER_OK, SUGGEST_OK]
mode sense (10): transport: Host_status=0x07 [DID_ERROR]
Driver_status=0x00 [DRIVER_OK, SUGGEST_OK]
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How can I fix io? Tnx
