Early this morning our sar reports show that WIO on the system was over 50% for about an hour. We also had some users complain about response time problems during this time. Is there a way I can go back and check what disks were busy during this time (something like topas but for historical data)? (1 Reply)
Hi
I have a requirement to list the files & the total disk utilization they have which are 10 prior to current date.
I tried couple of options in combinations of find mtime, ctime with du -m, but no luck.
Could you please help me in this ? (2 Replies)
Hi,
I have monitored that disk utilization is very high on one of red hat linux VM.
Would like to know how to find out that issue of high disk utilization is because of disk or Installed Application on that server is causing the problem.
Regards,
Manoj (1 Reply)
Hi,
I need help to write a script which will monitor disk utilization.
Please suggest the best approach to achive this.
I am thinking of having sleep inside the script which will run for(eg.) 60 secs and then disk utilization will be checked and depends on the % usage of disk mail will... (1 Reply)
Hi,
I wrote the following script for monitoring disk space and inform the concerned team accordingly. But script gives me below error
syntax error at line 70 : `<' unmatched
#!/bin/ksh
. /home/scr/.profile
. /home/scr/.infa_env
# Get the list of Integration Services
... (6 Replies)
Dear Gentleman
in my environment I have Solaris10 OS Box in Global Zone with 136 GB and mount point from SAN Storage 500 GB (Orastorage)
Zone1 mounted on /Zones folder with 66 GB
when I run zpool list output
-bash-3.00$ zpool list
NAME SIZE ALLOC FREE CAP HEALTH... (0 Replies)
Hi,
I have hundred folders under a fs /apps which is used by different users and they upload their data to these folders on a daily basis.
Using du -sk gives me complete structure of the filesystem but i want to find out day to day utlization of the top ten highest accoriding to size wise
... (4 Replies)
Hi Fiends,
I am new to scripting., I want to calculate the 2nd column in the below output and print the average for each hdisk.
Below is the output of sar command,
hdisk0 0
hdisk0 2
hdisk0 0
hdisk1 2
hdisk1 2
hdisk1 2
hdisk2 1
hdisk2 0
hdisk2 0
Thanks,
Srinivasan (3 Replies)
Hi All,
I am using SSH Tectia terminal to get the disk space utilization of a particular folder /opt/logs in all the servers one by one using the command df -h and looking through the list of folders manually to get /opt/logs folder disk space used percentage .
The problem here is , it... (2 Replies)
how to check overall hard disk utilization in unix?
we use bdf command to find the utilized space for the particular path
bdf filepath
how can i find overall hard disk utilization? (4 Replies)
Discussion started by: ashwanthfrq
4 Replies
LEARN ABOUT CENTOS
mpage_readpages
MPAGE_READPAGES(9) The Linux VFS MPAGE_READPAGES(9)NAME
mpage_readpages - populate an address space with some pages & start reads against them
SYNOPSIS
int mpage_readpages(struct address_space * mapping, struct list_head * pages, unsigned nr_pages, get_block_t get_block);
ARGUMENTS
mapping
the address_space
pages
The address of a list_head which contains the target pages. These pages have their ->index populated and are otherwise uninitialised.
The page at pages->prev has the lowest file offset, and reads should be issued in pages->prev to pages->next order.
nr_pages
The number of pages at *pages
get_block
The filesystem's block mapper function.
DESCRIPTION
This function walks the pages and the blocks within each page, building and emitting large BIOs.
If anything unusual happens, such as:
- encountering a page which has buffers - encountering a page which has a non-hole after a hole - encountering a page with non-contiguous
blocks
then this code just gives up and calls the buffer_head-based read function. It does handle a page which has holes at the end - that is a
common case: the end-of-file on blocksize < PAGE_CACHE_SIZE setups.
BH_BOUNDARY EXPLANATION
There is a problem. The mpage read code assembles several pages, gets all their disk mappings, and then submits them all. That's fine, but
obtaining the disk mappings may require I/O. Reads of indirect blocks, for example.
So an mpage read of the first 16 blocks of an ext2 file will cause I/O to be
SUBMITTED IN THE FOLLOWING ORDER
12 0 1 2 3 4 5 6 7 8 9 10 11 13 14 15 16
because the indirect block has to be read to get the mappings of blocks 13,14,15,16. Obviously, this impacts performance.
So what we do it to allow the filesystem's get_block function to set BH_Boundary when it maps block 11. BH_Boundary says: mapping of the
block after this one will require I/O against a block which is probably close to this one. So you should push what I/O you have currently
accumulated.
This all causes the disk requests to be issued in the correct order.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 MPAGE_READPAGES(9)