All,
I am attempting to help tune a Sun for better performance (mainly for SAS 9.1), and have found indicators pointing to poor I/O utilization. I have run iostat -cx, and found one device in particular where the %w is in the 90's during processing. I have a feeling that this is where the SAS... (3 Replies)
I'm search for a disk exerciser / load tool like iometer, iozone, diskx for IBM AIX 5.2 and 5.3
Because of a very bad disk performance on several AIX systems, I need to have a tool which is able to generate a disk load on my local and SAN disks.
Does somebody knows a kind of tool which is... (5 Replies)
Friends.
I have to compare iostat -x output with a tool on solaris. Now there is column called wait in the output field which is showing zero. Now, in order to create some load on my system this is what i am doing
I am creating a file using dd command , the size of which is... (5 Replies)
Hello,
On Solaris 10, iostat -E gives me the following results:
sd1 Soft Errors: 0 Hard Errors: 0 Transport Errors: 0
Vendor: FUJITSU Product: MAY2073RCSUN72G Revision: 0501 Serial No: 0708S08M2L
Size: 73.40GB <73400057856 bytes>
Media Error: 0 Device Not Ready: 0 No Device: 0... (1 Reply)
Hi, can anyone please suggest a tool to dump i/o packets just like tcpdump does for network traffic. Basically I have a complex dataflow that needs to be optimized and I want to see how packets go to/from disk - what goes randomly and sequentially.
Thanks (8 Replies)
A find for the "iostat" command on a redhat 5 update 4 comes back with no results.
Any separate rpm needs to be installed to get the binary for this ?
Thanks in advance. (1 Reply)
Writing a Tool to simulate non-sequential disk I/O (simulate db file sequential read) in C POSIX
I have over the years come across the same issue a couple of times, and it normally is that the read speed on SAN is absolutely atrocious when doing non-sequential I/O to the disks. Problem being of... (7 Replies)
Hello everyone,
Can you please explain me what kind of information do IOSTAT show ?
iostat -xnz 3 show me those informations:
The I/O of the c0t0d0 disk is normal ?
extended device statistics
r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b device
0.0 ... (3 Replies)
Hello, I support Oracle 11g on AIX 7.1.
Using the command
$iostat -D hdisk2 hdisk4 hdisk5 5
I get the following output:
hdisk5 xfer: %tm_act bps tps bread bwrtn
44.0 1.4M 178.2 1.4M 14.7K
read: ... (3 Replies)
Hi Everyone,
I try to calculate the total hard disk space of a solaris machine using iostat -En command. Iterating the output and summing up all the number present near the Size: will give the exact size of the harddisk. But it is not working for a machine.
This command works in many flavors... (2 Replies)
Discussion started by: prasankn
2 Replies
LEARN ABOUT REDHAT
lvscan
LVSCAN(8) System Manager's Manual LVSCAN(8)NAME
lvscan - scan (all disks) for logical volumes
SYNOPSIS
lvscan [-b|--blockdevice] [-d|--debug] [-D|--disk] [-h|--help] [-v|--verbose]
DESCRIPTION
lvscan scans all known volume groups or all supported LVM block devices in the system for defined logical volumes.
OPTIONS
-b, --blockdevice
Adds the device major and minor numbers to the display of each logical volume.
-d, --debug
Enables additional debugging output (if compiled with DEBUG).
-D, --disk
Scan for logical volumes on disk(s) instead of getting the information from the kernel.
-h, --help
Print a usage message on standard output and exit successfully.
-v, --verbose
Gives verbose runtime information about lvscan's activities.
--version
Prints version number of tool and exits sucessfully.
DIAGNOSTICS
lvscan returns an exit code of 0 for success and > 0 for error:
1 no volume groups found
2 invalid volume group name
3 error getting VGDA from kernel
95 driver/module not in kernel
96 invalid I/O protocol version
97 error locking logical volume manager
98 invalid lvmtab (run vgscan(8))
99 invalid command line
SEE ALSO lvm(8), lvcreate(8), lvdisplay(8)AUTHOR
Heinz Mauelshagen <Linux-LVM@Sistina.com>
Heinz Mauelshagen LVM TOOLS LVSCAN(8)