Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Raid0 array stresses only 1 disk out of 3
Top Forums UNIX for Dummies Questions & Answers Raid0 array stresses only 1 disk out of 3 Post 302970987 by chebarbudo on Thursday 14th of April 2016 10:45:21 AM
Old 04-14-2016
Hi guys,

Thank you very much for your contributions.

First of all, my problem does not happen any more. I created the raid with sdb, sdc and sdd on April 11 at 09:35.
Until 11:32, sdd was very busy, then until 14:51, sdc was very busy.
Since then (3 days), the 3 disks are always under the same moderate load altogether (0-20%). The server is used by 5 graphic designers manipulating quite large files (100M-2G).

I ran some tests and the results leave me quite puzzled. So I created simultaneously 10 files. 1GB each. But all the load went on sda. Leaving sdb, sdc and sdd with a moderate 20% load.

The command:
Code:
for i in {1..10}; do
  file=$(mktemp /galaxy/XXXXXXX)
  echo $file >> /galaxy/dd.files
  dd if=/dev/zero of=$file bs=1G count=1 &
  echo $!    >> /galaxy/dd.pids
done

The output of dstat:
Code:
----system---- sda--sdb--sdc--sdd-
     time     |util:util:util:util
14-04 15:56:30|  21:   0:   0:   0
14-04 15:57:00| 100:   0:   0:   0
14-04 15:57:30| 101:   0:   0:   0
14-04 15:58:00| 100:   2:   2:   1
14-04 15:58:30| 101:   3:   4:   2
14-04 15:59:00| 102:   4:   5:   4
14-04 15:59:30|  98:   2:   3:   2
14-04 16:00:00| 100:   4:   4:   2
14-04 16:00:30| 103:  16:  16:  15
14-04 16:01:00|  98:  16:  17:  15
14-04 16:01:30| 101:  15:  15:  15
14-04 16:02:00|  99:   9:   8:   8
14-04 16:02:30| 100:   3:   4:   3
14-04 16:03:00| 100:   2:   4:   3
14-04 16:03:30| 104:   4:   4:   3
14-04 16:04:00|  95:   4:   4:   3
14-04 16:04:30| 100:   3:   4:   2
14-04 16:05:00| 101:   3:   4:   3
14-04 16:05:30|  99:  12:  13:  12
14-04 16:06:00| 102:  20:  22:  18
14-04 16:06:30|  98:  17:  19:  18
14-04 16:07:00| 101:   7:   9:   8
14-04 16:07:30|  99:   4:   5:   3
14-04 16:08:00| 102:   4:   5:   3
14-04 16:08:30|  98:   3:   5:   3
14-04 16:09:00| 100:   5:   7:   5
14-04 16:09:30| 101:   5:   5:   4
14-04 16:10:00| 100:   4:   4:   2
14-04 16:10:30| 100:  17:  18:  16
14-04 16:11:01| 105:  16:  20:  16
14-04 16:11:30|  95:  15:  17:  17
14-04 16:12:00| 100:  12:  11:  10
14-04 16:12:30|  34:  15:  16:  14

Is /dev/zero an actual file of sda?
How do you interpret the results?

Regards
Santiago
 

9 More Discussions You Might Find Interesting

1. Solaris

A1000 Disk storage array

I am new to the unix world. I have SunBlade 100 and A1000 Disk storage array with 12 Hard drives. I used SCSI card and SCSI cables to connect. When I do the format command,I can see disk storage as one disk instead of 12 disks as below. Could anybody can explain why? What should I do in order... (1 Reply)
Discussion started by: Dulasi
1 Replies

2. Solaris

Solaris RAID0 doubt...

friends, Suppose I am typing metastat command and it is showing: d100: Concat/Stripe Size: 369495 blocks (180 MB) Stripe 0: (interlace: 32 blocks) Device Start Block Dbase Reloc c1d0s0 16065 Yes Yes c1d0s1 0 No Yes... (4 Replies)
Discussion started by: saagar
4 Replies

3. UNIX for Advanced & Expert Users

3510 Disk Array Problem

I have a 3510 disk array attached to a T2000 server. The dmesg command shows disk error as follows and is generated a couple of times during the day Aug 18 03:35:51 myserver SUNWscsdMonitor: <rctrl6042> Standard General Event, CHL:2 ID:22 Drive NOTICE: Drive Recovered Error - 5F8E1F... (1 Reply)
Discussion started by: Tirmazi
1 Replies

4. Linux

Raid0 recovery from external HD

Hi, I have the Lacie Big Disk, which is a external hard drive enclosure in a hardware RAID0 array of 2x250GB disks. The RAID controller seems to have died, leaving me with 2 working hard drives but no way to get the data. I tried hooking the drives up to a windows machine and using Raid... (4 Replies)
Discussion started by: dangral
4 Replies

5. UNIX for Dummies Questions & Answers

Why is RAID0 faster?

I have read anecdotes about people installing RAID0 (RAID - Wikipedia, the free encyclopedia) on some of their machines because it gives a performance boost. Because bandwidth on the motherboard is limited, can someone explain exactly why it should be faster? (7 Replies)
Discussion started by: figaro
7 Replies

6. Solaris

Disk Array

So I have 2 solaris sun servers one with a disk array with 14 drives which I need to move to the other server. How do I move the disk array configured as a Raid 5 to another server without losing data? So far I know I'll connect the drive, run devfsadm, use format to verify the server see's... (5 Replies)
Discussion started by: Kjons76
5 Replies

7. UNIX for Advanced & Expert Users

Disk Array

HI: I have a DUAL redundant system running in HP-UX 10.20 ( 2 servers) Both servers share an external SCSI disk array. Both server runs a Data base wich uses the disk array to write the data, and that is the way they share the information. The way that the servers see the disk array, is like... (1 Reply)
Discussion started by: pmoren
1 Replies

8. Filesystems, Disks and Memory

DISK ARRAY PROTECTION SUSPENDED message displayed following disk replacement

Hello, On 4/20/2018, we performed a disk replacement on our IBM 8202 P7 server. After the disk was rebuilt, the SAS Disk Array sissas0 showed a status of degraded. However, the pdisks in the array all show a status of active. We did see a message in errpt. DISK ARRAY PROTECTION SUSPENDED. ... (1 Reply)
Discussion started by: terrya
1 Replies

9. AIX

DISK ARRAY PROTECTION SUSPENDED message following disk replacement

Hello, On 4/20/2018, we performed a disk replacement on our IBM 8202 P7 server. After the disk was rebuilt, the SAS Disk Array sissas0 showed a status of degraded. However, the pdisks in the array all show a status of active. We did see a message in errpt. DISK ARRAY PROTECTION SUSPENDED. ... (3 Replies)
Discussion started by: terrya
3 Replies

LEARN ABOUT FREEBSD

vgimportclone

VGIMPORTCLONE(8)					      System Manager's Manual						  VGIMPORTCLONE(8)

NAME

       vgimportclone - import and rename duplicated volume group (e.g. a hardware snapshot)

SYNOPSIS

       vgimportclone [-n|--basevgname VolumeGroupName] [-i|--import] PhysicalVolume [PhysicalVolume...]

DESCRIPTION

       vgimportclone is used to import a duplicated VG (e.g. hardware snapshot).  Duplicate VG(s) and PV(s) are not able to be used until they are
       made to coexist with the origin VG(s) and PV(s).  vgimportclone renames the VG associated with the specified PV(s) and changes the  associ-
       ated VG and PV UUIDs.

OPTIONS

       See lvm for common options.

       -n|--basevgname VolumeGroupName
	      By  default  the	snapshot  VG  will be renamed to the original name plus a numeric suffix to avoid duplicate naming (e.g. 'test_vg'
	      would be renamed to 'test_vg1').	This option will override the base VG name that is used for all  VG  renames.	If  a  VG  already
	      exists with the specified name a numeric suffix will be added (like the previous example) to make it unique.

       -i|--import
	      Import exported Volume Groups.  Otherwise VGs that have been exported will not be changed (nor will their associated PVs).

ENVIRONMENT VARIABLES

       LVM_BINARY
	      The LVM2 binary to use.  Defaults to "lvm".

EXAMPLES

       The  origin VG vg00 has origin PVs /dev/sda and /dev/sdb and the respective snapshot PVs are /dev/sdc and /dev/sdd.  To rename the VG asso-
       ciated with /dev/sdc and /dev/sdd from vg00 to vg00_snap (and to change associated VG and PV UUIDs) do:

	    vgimportclone --basevgname vg00_snap /dev/sdc /dev/sdd

SEE ALSO

       lvm(8)

Red Hat, Inc.						 LVM TOOLS 2.02.95(2) (2012-03-06)					  VGIMPORTCLONE(8)
All times are GMT -4. The time now is 05:56 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy