I attended many interviews for Linux Admin post. Most of them asked me a common question 'How do you handle System Performance Issues' on a Linux Server. Now how do I answer this?
View 12 RepliesI have doubts regarding storage:
How to configure the Events of Storage Processor?
What are performance issues will come daily in a critical production server?
What are first steps for disk performance Check?
What are first steps for Storage Processor performance Check?
What are first steps for MetaLUN performance Check?
Is there a terminal command to monitor CPU and/or RAM usage?
View 8 Replies View RelatedIn the man page for find there is an example for deleting core files from /tmp: find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f
which I am sure does what was intended. However, this very similar command does something quite different: find /tmp -print0 -name core -type f | xargs -0 /bin/rm -f
This actually removes all files in /tmp, ignoring the -name and -type arguments. I checked the man page to see if it detailed this behaviour, but the only reference to the order of the arguments was that -name should come before -type to prevent excessive calls to stat(2) on all files. This seems very risky behaviour on the part of find and I am concerned about whether this is a bug or not. I wasn't trying to remove core files from /tmp when I found this out, but deleting other files from another part of the filesystem .
how does this operating system handle and avoid deadlocks? i m familiar with theoretical documentation of deadlocks. how/which methods are practically used by SUSE to handle and avoid deadlocks. how is deadlock but nothing which say SUSE IMPLEMENTS THESE METHODS for DEADLOCK avoidance...)
View 3 Replies View RelatedI install KDM cause I couldn't run fglrx on GDM since i install the drivers of my GPU and the KDM ... I am suffering from poor system performance youtube videos mostly HD run very laggy and overall performance decreased ...
I run lxde ....
Basically I'm wondering if there is any way to lighten Gnome and Ubuntu I would like to keep Gnome if possible. I am a pretty experienced linux (or for you hardcore GNU fans GNU/Linux) user having used it for almost 4 years and I just built my Arch system but have found that alot of the functionality that I've come to love about ubuntu isn't in the default Gnome package but that Ubuntu's Gnome is heavily modified so I want to switch back but do to my lack of modern hardware I can't run Ubuntu as smoothly as I want.
Below is my current hardware.
Code:
Intel Pentium III 733mhz
512mb of ram
8gb Hard Drive
and a Dvd Drive
Nvidia Geforce 6600 265mb pci gpu
100 watt power supply
I am also a Developer so I know I can compile the Kernel my self and remove some not needed junk and optimize it. But I was wondering are there some Highly intensive processes that don't really need to be running? The only thing I would be using Ubuntu for is Web Browsing, Coding, Gimp, Text Processing and probably Music; thats really all I need I don't do much else besides that.
tl;dr:
Basically all I'm trying to do is lighten Ubuntu and Gnome without putting 3 days worth of work into it.
I have an older PC running Ubuntu 10.04, and the system is slow, especially with Firefox running. I recently upgraded to 2 gig memory, but it didn't help. I have plenty of space on my hard-drive, using only 30 gig of 80 gig. My CPU is Intel Celeron 2.40GHz. I have broadband, and the speed seems good. What are the system requirements for Ubuntu 10.04? Any tips for speeding performance, esp on Firefox? I used to do a defrag when I had Windows; is there any need to do that on Ubuntu also?
View 9 Replies View RelatedI need evaluate the ext3 file system performance; i need define:
- services provided
- parameters and
- the performance with different parameter values; for example, changin the value of the "data" parameter (journal, ordered, writeback).
I do not know what services ext3 provides. Well, i know intuitively that it provides services to read, write and erase files. But, there are anything more?. Where can i find the API?. Is the ext3 file system POSIX compliant?
Last I upgraded one of our cent 5 boxes which is running kvm with a mix of centos and windows VMs.After the update performance just tanked on the XP guest, but the others (including other windows VMs) are just fine.I checked with our good friend google and didn't really get any help there.We're hoping to NOT have to rebuild the XP guest, so I thought I'd check in here first.
This is CentOS release 5.5 (Final) with kernel
2.6.18-194.32.1.el5 #1 SMP (64bit)
I am running the newest linux (ubunbtu 11.04) on an old laptop (2.3 Ghz celeron, 760 mb ram, bios is the latest version). I don't expect it to perform well, it's not a fast processor.But.....it performs so poorly with linux...and I am beginning to wonder whether the machine is broken or malfunctioning. The processor utilization seems high at all times, but I am not sure what is normal/typical.Which of the many benchmark software packages should I use in order to quantify it's performance (or lack there of)? Are there web resources that will list benchmark values of various machines, so I can determine if my punch box is broken or whether it's just slightly slower than other similar machines?
View 3 Replies View RelatedI just wanted to know if having my laptop set to ondemand, will this affect performance in any way? I realize it increases the clock speed to performance when the CPU is under load, but does the time it take to go from ondemand to performance affect speed? Will there be any noticeable difference between the two setups? I have a dual core intel at 2.2GHz when in performance. When ondemand is set with no load it downclocks to 800Mhz.
View 7 Replies View RelatedI have a 20TB filesystem, xfs formatted. The filesystem has been mounted with the inode64 option, and I now need to NFS export it. NFS doesn't like the inode64 option at all. The NFS clients cannot access any of the directories with inode numbers exceeding the 32bit limit. They get the "Stale NFS file handle" message. I have tried to attach the filesystem to a RHEL5.3 system, and after turning on the no_subtree_check option in /etc/exports on the server, it all works fine. No changes were needed on the clients.
The problem is that I need to get this to work on a RHEL4.4 system. Unfortunately I cannot do any test on that system yet, I then did a quick test on a RHEL4.3 system... and it didn't work. Even using the no_subtree_check option was on any help. I am afraid that this will not work on the RHEL4.4 system either. How to get the inode64 xfs filesystem NFS exported on a 2.6.9 kernel?
There is not a lot of info on that command, I didn't find a manpage nor a info and not more than examples on the web. Is there any tutorial or info on internet?
View 2 Replies View RelatedI've been trying to understand issues that occur during a uClinux distribution build (so I can include such issues in a module I'm writing for students). My process has been to work through errors that occur due to missing packages, then remove the distribution and build it again to uncover what happens.One thing I notice is different sets of warnings within each iteration of making a new build. From the document here (URl...it states, "A typical warning involves a variable being used before its value has been set."
So my question: is there a way to verify that the issue throwing the warning has been resolved by the end of the make build?And, is running make build again an option or could this cause problems within the build directories or image?
We have setup a High Available Cluster on two RHEL 5.4 machines with Redhat Cluster Suite (RHCS) having following configuration.
1. Both machines have Mysql server, Apache web server and Zabbix server.
2. Mysql database and web pages reside in SAN.
3. Active machine holds virtual IP and mounted shared disk.
4. We have also included a script in RHCS which takes care of starting Mysql, Apache and zabbix server on the machine which turns active when cluster switches over.
The above configuration holds good if Active machine goes down as a result of hardware failure or Reboot. What if, If any one service say Apache/Mysql/zabbix running on active hangs or become unresponsive.How can we handle this scenario ? Please advice.
Where to get a plugin to handle *.zip files
View 2 Replies View RelatedI recently installed another harddrive into my Arch Linux computer. The first time I booted up all worked fine. The next time I restarted my computer though I was greeted with a /dev/sda2 not found error.
See, basically sometimes my boot harddrive is sda and sometimes it's sdb. It appears to be completely random and I don't see any options for making it non-random in the BIOS. How do I fix this?
cwrsync is a great tool for synching "My Documents" to a network drive in Windows. However it uses a portion of cygwin to do this which uses forward slashes instead of back slashes. So, a manually typed command like the following works great: rsync -r --delete --exclude "My Pictures" "/cygdrive/c/Documents and Settings/demo/My Documents/" /cygdrive/j
However, you cannot put a variable like %userprofile% in this as it comes out like this (and is unrecognized): rsync: change_dir "/cygdrive/C:Documents and Settingsdemo/My Documents" failed: No such file or directory (2)
i have a script where i need to pass an argument "1234:-)"if i run this as ./shell.sh 1234:-)it wont work because invalid character. i need to handle this with expect utility so if i pass it as ./shell.sh "1234:-)"no issue in bash but expect does not recognize this.
View 7 Replies View RelatedI am experiencing weird problem with Gnome 2.30.2 on my Debian installation. I can't open "Computer" from places, also, partitions which are not explicitly defined in fstab are not mounted automatically.
View 2 Replies View RelatedI did a backup of the ssd on my eeepc using the following command from a Linux Mint on a USB key:
dd if=/dev/sda1 of=/media/disk/eeepc_save/SYSTEM/system.bck
(/media/disk in an external USB disk)
I deleted the ext2 partition using GPartEd on live USB key and created it back. I rebooted Linux Mint and restored the filesystem using the opposite command :
dd if=/media/disk/eeepc_save/SYSTEM/system.bck of=/dev/sda1
I mounted /dev/sda1 and when I "ls" the root directory, I get several "NFS stale file handle" messages concerning directories (/dev and other). I tried "e2fsck -y", had a bundle of corrections that resulted in the deletion of the directories. I don't use NFS. I did the same for the user filesystem and had no problem (it's an ext3 partition). The two filesystems are the ones that came with the original Xandros installed on my eeepc and that were mounted with union-fs.
I would very much appreciate infos about a Linux distro handling win32 applications through wine and easily capacity to manage files within FAT32 partitions.
View 7 Replies View Related1.- What would be the simplest way to port and handle tarballs downloaded in windows, to a CentOS 5.4 based system (Elastix in fact), but without graphic mode (that is, using only the CLI)? The system has network contection, usb interfaces and a working DVD-RW attached.
2.- If the answer is Samba, how I get Samba working on my system?
* I am implementing mass storage device on a test board.
* It contains NAND flash.
* Using corresponding "udc driver" and "g_file_storage" I could make my test board enumerate as mass storage device on my Linux machine.
* my 16 MB pen drive (test board) is now ready for read/write.
But there are some Bad Blocks on the NAND.Hence copy is not complete. Although on Linux machine there is no error message. Now , what is there in a normal pen drive which manages the Bad Block or what am I missing so that such Bad Blocks are managed.
Here is the error I get on my test board :
mtdblock: erase of region [0x2c0000, 0x4000] on "Bon 2" failed
end_request: I/O error, dev mtdblock2, sector 5664
Buffer I/O error on device mtdblock2, logical block 708
[code]....
I am proposing moving from the mainframe to Linux. Problem is that I am not aware of a scheduling product that is available to handle the production code. Currently using CA7. Is there anything out there that accomplishes the same thing? As you can tell, I am NEW to Linux!
View 1 Replies View RelatedWe have Linux server in our environment for application development. In this server we mounted so many NFS share from Storage. Past few days we receive this error in
syslog kernel: nfs_statfs64: statfs error = 116
Some user fased this error "Stale NFS file handle"
Server info
OS= RedHat
Kernel = Linux hostname 2.4.21-47.ELsmp #1 SMP Wed Jul 5 20:38:41 EDT 2006 i686 i686 i386 GNU/Linux
Currently running Slackware 13.37 64-bit on a notebook and finally have suspend/hibernate after realizing that USB devices, especially USB HDDs, need to be disconnected before suspend/hibernate can work. Problem is I have 2 USB HDDs that are connected to my notebook whenever the notebook is stationary for the extra storage so I'd like to create a script that would get invoked that would stop the suspend/hibernate process if certain partitions are mounted. I know what I would like to accomplish, but I have basic scripting knowledge so I was hoping to get some assistance.
1. script would basically store a user specified string containing devices that are non-USB, ie: NONUSB="/dev/sda /dev/sdb"
2. possibly use /etc/mtab to get a list of what is currently mounted and then remove lines containing whatever is specified in $NONUSB and store those values in $USB
3. run a for loop that executes 'umount' on each token in $USB
3a. stop suspend/hibernate process if 'umount' fails at any point
3b. if 'umount' passes then suspend/hibernate
I get this error which means I cant visit websites. I cant rm, cp, mv, vi, ... this file. How do I regain the ability to browse the internet? Is there a way I can create a /etc/resolv.conf2 and have my system use that instead?
View 4 Replies View RelatedI have a weird performance issue with a centos 5 running a nfs server and a rh8 client. I think the fact that it is rh8 client should be downplayed. It is just that with rh8 client the performance degradation seems more clear. See test details below OS in server is Centos 5 x86_64 kernel 2.6.18-92.1.22.el5
1Gb connection between machines File to test over NFS is a 1GB file. First of all I wanted to measure how the network alone performs while using NFS. So in the server side I run a "cat" command on the 1GB file to /dev/null. Please note that the disk read speed is about 98MBs. At this point the file system has the 1GB file cached in memory. In the client side a "cat" on the same file gives me a speed of about 113MBs. It seems then that the bottleneck in this instance is the network and it is very close to nominal speed. So the network performance is really good. (BTW I know that the server got that file from cache because a vmstat or iostat shows no disk activity.)
The second test is reading from disk with no caching involve. In the server I flushed the 1GB file from the memory. For instance by reading another 5GB file and I repeat the same thing as above in the client (a cat on the 1GB file). Now, the server has to go to disk.(vmstat or iostat shows the disk activity). However the performance, now, is about 20MBs, I was expecting something closer so 90MBs. (since the reading speed in the server in the first test showed 98MBs).
This second test was repeated for ext2, ext3, xfs with no significant differences. A similar test using a RH8 NFS server and client gets me close to 60MBs for a 1GB file not cache by the file system in the serverSince network speeds and disk read speeds are not the bottlenecks ... what or where is the limiting factor then?