Is there a way to determine the IO size that is being used for reads and writes to an attached storage device? I am trying to pattern the IO sequences to storage. I have seen mentions to max_sectors_kb but the notes indicated that changing this value did not change the IO size to the storage.
View 1 RepliesI have a 6 disk mdadm RAID 10 array of Western Digital RE3 drives. IOZone and all the other tools I have tried are showing pretty lackluster reads for a six drive RAID 10 array, in the area of 200MB/s. Writes are closer to what I'd expect in that area, around 340MB/s. These drives fly with an Adaptec RAID controller, but as soon as I stick them in an mdadm array, the reads just aren't what I'd expect.
I am using what I believe to be optimal settings:
-C /dev/md2 --chunk=1024 -n 6 -l 10 -p f2 /dev/sda5 /dev/sdb5 /dev/sdc5 /dev/sdd5 /dev/sde5 /dev/sdf5
-b 4096 -E stride=256,stripe-width=768
We are graphing various system parameters using Cacti. One of our graphs shows hard drive reads and writes. A question came up: why do we need this graph?
View 3 Replies View RelatedI have a fileserver running 10.04 server 64bit and samba. I connect it to my desktop which is 10.04 desktop 64bit.I have the server mounted on my desktop in fstab as://10.0.0.2/share /media/share cifs guest, uid= 1000.Up until 30 June 2010 it was all fine. Now when I write the server it is very slow e.g. 2Mbps though when I read I get >100Mbps so I think my network is still ok. If i use nautilus smb://10.0.0.2/share I can write at >100Mbps and also read at >100Mbps...So any ideas why the write speed via the fstab mount samba has started to go really slowly in the last couple of days?
View 6 Replies View RelatedIs there already a program that reads multiple pipes or file descriptors and writes to the standard output (not splitting lines).Like cat, but reading all files simultaneously and preserving lines.It is needed to avoid coding of select/epoll loops or using multithreading in simple programs. Like "select loop for bash".
View 1 Replies View RelatedWhen CentOS boots up, it tries to determine the IP for a network device (eth0) and fails.
'Determining IP information for eth0... failed; no link present.'
I'm curious to know how, after booting up, I could set the IP information for a wireless device, wlan0, manually. Another way of putting this questions is: if CentOS is able to determine IP information for a network device on bootup, what settings is it configuring exactly?
you have to read from many devices separate devices and make it look like a single one. It sounds very much like a device driver to me, perhaps... but getting my hands dirty with kernel code sounds like a daunting task for me that I've never done it...
View 2 Replies View Relatedhere we have an older digicam (Jenoptik/Exakta Model "DC 22", if someone might want to know) that can be switched between some "PC Camera mode" and "Mass storage mode".Unfortunately, if attached to USB, it is always recognized as
Code:
UDEV [1262910483.475886] add /class/video4linux/video0 (video4linux)
lsusb tells:
[code]...
I was analyzing the Disk read using hdparm utility. This is what i got as a result.
Code:
# hdparm -t /dev/sda
/dev/sda:
Timing buffered disk reads: 108 MB in 3.04 seconds = 35.51 MB/sec
Code:
# hdparm -T /dev/sda
/dev/sda:
Timing cached reads: 3496 MB in 1.99 seconds = 1756.56 MB/sec I m not sure what does Cache read and buffered disk read mean.
i want to change the mtu size of my ethernet controller. I have done successfully set the mtu size 9000 for broadcom net xtreme PCI: 66 Mhz 64 bit 1 gigabit card. (fibre)
Part model no: BCM95703A31
[root@lux08 ~]# ethtool eth0Settings for eth0:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseT/Half 1000baseT/Full
Supports auto-negotiation: Yes
[Code]....
how to change the mtu size for this NIC?
I just compiled my first own kernel (I'm using Arch Linux), following the tutorial on the german site. Now I tried to boot it, I ended up failing with this message: Code: Waiting 10 seconds for device /dev/sda1 ... Root device '/dev/sda1' doesn't exist, Attempting to create it. ERROR: Unable to determine major/minor number of root device '/dev/sda1' Here is the important part of my menu.lst:
[Code]....
I simply copy&pasted the Arch-entry, i.e. I also had the disk by uuid there. The failure message was the same, just the root device name was the different name Also, at first I did not have the initrd line in my menu.lst (as written in my tutorial that I may not need it). In this case I had this error message:
[Code]....
Multiple dirs full of mp3s All strictly encoded with exactly the same parameters (CBR 128kbps, Joint-Stereo, etc) Is it possible to determine the total playing time (to within ~98% accuracy) by some formula based on the total file size? I say ~98% accurate since ID3 tags do consume a small amount of space.
View 3 Replies View Relatedi have a folder with 10 files and i would like to determine the size of each file. i was trying the command
Code:
du -sh foldername
but i receive the total size .
I have the following which works but think there must be a easier one-liner way of doing this which involves not writing to a file but have failed to find something that works This is what I have:
Code:
du -m $i > filesize.txt
FILESIZE=$`cat "filesize.txt" | cut -f1
rm filesize.txt
I then use the FILESIZE to compare to a number.
I'm working on a project using CentOs 5.3 that uses a solid state drive (SSD) as the boot device. It is desired to configure it such that writes do not typically occur run-time but configuration files can be saved. There are 2 reasons we do not want writes to occur run-time. 1) Writes will wear out a SSD over time. 2) A system disruption during a write can cause a file system error.
View 3 Replies View RelatedWhen I try to burn some .flv files onto a DVD iso using K3B, it gives me the message: "Could not determine size of resulting image file"
View 1 Replies View Related[root@zhuhaiping MPlayer-1.0rc2]#./configure --prefix=/opt/mplayer --enable-gui --enable-freetype --codecsdir=/opt/mplayer/codecs --win32codecsdir=/opt/mplayer/wincodecs/ --language=zh_CN
it's ok ,but when I configure like this
[code]....
But when I make there comes this problem which as follows ;
vo_ivtv.c: In function 'ivtv_reset':
vo_ivtv.c:79: error: storage size of 'sd' isn't known
vo_ivtv.c:80: error: storage size of 'sd1' isn't known
[code].....
When I run apps like mplayer to use my web cam it uses /dev/video#. For reason unknown to me this number changes and is usually either 1 or 0. I have looked on the Internet after struggling to find how to know which /dev/video device is used. So far I can only presume I have used the wrong terms to find how to determine which device the web cam is using.
View 5 Replies View RelatedI want to generate a temporary random list from a directory of files and then determine the size of an arbitrary block of files from this list (say 1-25 or 26-50) and add their names to a file along with some other info for each name. I can generate a random list with file sizes like this: ls -l | sort -R | cut -d " " -f 6 but i'm not sure how to add up the sizes of just a certain block of these files and at the same time save the file names.
View 2 Replies View RelatedIs there a command to determine of a device supports IO Fencing?We are trying to run a Sybase cluster that shares storage. I'm sure the device supports fencing, but don't know how to show that it does.
View 1 Replies View RelatedI'm currently running Ubuntu (w/ GRUB) and Windows XP. I'd like to remove Ubuntu and run the recovery on Windows XP because it has started not running correctly. The computer is about 5 years old and I figured I'd just wipe it clean and start over (read: remove Ubuntu and reinstall windows via the recovery console).
I intend to follow the tutorial here: [URL]
However, I'm confused about determining the boot device number for Windows. I've run "sudo fdisk -l" and I can identify the windows drive in the list it says:
Device: /dev/sda1
Boot: *
Start: 1
End: 19352
Blocks: 155444908+
Id: 7
System: HPFS/NTFS
Am I looking for the 7, the 1, or something completely different? This is also the first partition on the list.
sda2 (id: c) is a FAT32 drive. I think this is the recovery partition included on the HP desktop.
sda3 (id:83) is Linux
sda4 (id: 82) is swap
I just need to run fixmbr.
I'm writing a bash script that needs to know whether or not a device node is part of a RAID array. I'm just curious if anyone knows of a good way to determine if a device node is in a RAID array. I know that you can run mdadm -Q or mdadm --examine on the device node and that will tell you. But I don't want to rely on screen scrapping and would rather have something that would return a boolean. Any ideas?
View 2 Replies View Relatedis there a way or terminal command to disable access to a USB storage device upon insertion given that it is not permitted?
View 5 Replies View RelatedI'm in need to replace a harddrive with higher capacity one but I can't tell which bay is holding on to a drive which has the OS. I don't want to pull the main drive. just wondering if there is a way to light up the led light next to physical drive/bay so I don't accidentally yank out the wrong one.
View 4 Replies View RelatedI am using a Belkin F5D 8235-4 ver 2 wireless router. My linux box is connected direct. I have a 16G flash drive installed in the usb port on the router that I want to use for storage so I can dump files I share with my other machines on the network. Windows sees this usb and works fine by just using the web browser and using 192.168.2.1usb no problem. Then I try to use my unbuntu and can not for the life of me figure out how to set up a permanent link to that drive in linux. I would like to have a direct connection on my desktop. Of course I tried Belkin and was told we do not support Linux.
View 4 Replies View RelatedAre there any tools in Ubuntu that could defragment my MP4 player (Sansa E280R)? One of the songs on my MP4 player isn't showing its Album Name or Artist Name. I know I have the artist and album name tagged onto the MP3 because I set them both & double checked using mp3tag.
View 9 Replies View RelatedI am currently using opensuse 11.2 with kde 4.3.1. I am having a problem when I connect my samsung R450. It will not mount or show up as a usable device in either Dolphin, Amarok, or on the device notifier. I have tried manually mounting but I get an error saying it cannot find such device. I did not have any issues using it in 11.1 with KDE 4.2. It is being recognized by my system, but not allowing it to show up as a storage device or being mounted.
output of dmesg:
PHP Code:
output of lsusb:
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When I shut of the usb mass storage on the samsung R450 it switches to modem and is properly detected and usable as modem by my system.I don't have any other problems with other usb devices, such as a digital camera or flash drives, so I don't know if I just missing a system setting or configuring something wrong.
I just discovered that inserting any USB drive causes an immediate hang of the system. The keyboard caps lock and scroll lock lights blink. Only recourse is to power cycle the system. This is after installing Kubuntu 9.10 in January, I don't believe I had occasion to insert a USB drive until tonight. 100% reliable. No entries in logs, presumably because it hangs the kernel when it happens. The /var/log/kern.log file has been corrupted due to file system damage (1+ sectors of some other file inserted into chain) and probably other files as well.
I've not had occasion to report other bugs, but I've found no way to report anything other than application bugs. I tried using "ubuntu-bug kernel" which helpfully said there was no such application as 'kernel' and has been busy "collecting problem information" for the last half hour or more. Somehow I don't think its ever going to finish.
The crash only happens when booted into Kubuntu 9.10. If I boot off of 9.04 then USB drives work fine. Both USB drives I've tried reliably produce the crash. One is a random cheap USB thumb drive (imprinted "Cisco"), the other is a 16GB Corsair Voyager.
I had troubles with my NTFS external hdd mounting without becoming root until I changed my fstab file. However after changing my fstab file I created an error in the place of the one I had fixed. Now since the change I have two entries of my external hard drive in Places. I'd like to know how to remove the duplicate entry.
Provided is my current fstab and screenshot of duplicate:
Code:
# /etc/fstab: static file system information.
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
#Entry for /dev/sda1 :
UUID=219f23c6-9079-4297-a7b3-ee41a264780b
/ ext4 errors=remount-ro 0 1
#Entry for /dev/sdb1 :
UUID=486E622C6E62134C /media/Beast ntfs-3g auto, users,
uid=1000, gid=100, utf8, dmask=027, fmask=137 0 0
#Entry for /dev/sda5 :
UUID=064020c3-cf2f-4ba5-b0b6-49667fee4f27 none swap sw 0 0
I am trying to install dynabolic on my system by docking.I copied dyne/ directory into my partition and updated grub as follows:
title Dyne
root (hd0,0)
kernel (hd0,0)/dyne/2618ckld.krn root=/dev/ram0 rw load_ramdisk=1 prompt_ramdisk=0
ramdisk_start=0 max_loop=64 vga=788
initrd (hd0,0)/dyne/initrd.gz
Still on booting into it,it is saying "No storage device with dyne system found"
why this happens? On the otherhand it is automatically detecting my pendrive in which i have copied dyne/
and boots from it.