When I'm recompiling apache and php, it doesn't go through and I get this error:
Code:
checking for atomic.h... no
/usr/include/mysql/my_global.h:364:24: error: asm/atomic.h: No such file or directory
[code]....
have two shared variables a,b which are related to each other.When multiple applications share these shared variables, access to them needs to be an atomic operation, otherwise the relation may break. So to ensure mutual exclusion, I'll put their modification under a critical section protected by lock.
Code:
critical_code
{
P(mutex)
a := something
b := something
V(mutex)
}
Lets say my hardware/OS/compiler supports atomic variables. Then I modified my above code as follows.
Code:
code
{
atomic a := something
atomic b := something
}
Can this code ensure mutual exclusion, when accessed by multiple applications?
I wasn't sure if this is the right place to ask or comment on this, but since it's about Apache web server I thought it should work. I finally figured out how to set up and bring up the site using virtual hosts in Apache, though at the moment it's just for my localhost install.
I set them up so I can have a place to play with possible new themes and/or test out the Drupal 7 alpha / beta releases without messing up my current configuration. I decided to look at the error logs for the currently configured site and it had a lot of messages similar to the following:
[Sat Mar 06 09:45:39 2010] [error] [client 127.0.0.1] ModSecurity: Unable to retrieve collection (name "ip", key "127.0.0.1"). Use SecDataDir to define data directory first. [hostname "site.local"] [uri "/"] [unique_id "ZnUHgsCoAAEAABdzR2QAAAAB"]
I'm only somewhat new to linux but I still don't have a real grasp of it's deep innards and I had a fairly outlandish idea that I'm wondering whether is possible/plausible or not.I want to run a game server on CentOS that has a very high dependency on fast writes-to-disk. Disk writes are pretty much the single bottleneck in this server.First I looked at allowing a high queue of writes to pile up before it flushes them to the disk, but I read that this causes fsync, which is still used commonly, to take a very long time.
I've been thinking about the possibility of running the server on a RAM disk, but I still want changes to be saved to non-volatile storage. Not all at once, but have it actively write the changes to disk. The hope is that this would smooth out the peaks and valleys of write activity and improve overall performance, but I have not seen this idea discussed anywhere.
So my question is, is there any plausible way to continuously copy writes to a RAM disk to a physical drive without slowing down the speed of the writes to the RAM drive below the speed of said RAM? Or is there a better way to obtain this sort of performance, short of investing in expensive equipment?
I need to insure the "writer" to named shared memory (small size, 160 bytes) completes his task such that the many "readers" always get the latest data. The machine is a multi-processor (8 CPU, 24 Gig RAM), non-real time system. The system has multiple processes that are also multi-threaded. Thankfully, there is only 1 "writer" and many "readers". There is no semaphore or mutex locking. "Readers" must not block each other and especially not block the "writer".
By design, it is expected from time to time a "reader" will be in the middle of reading when the "writer" begins to update the data. I want to protect against the case of the "writer" being interrupted and a "reader" completes it's read before the "writer" wakes up and completes it's changes. In this case the "reader" will get corrupt data, some new and some old.
Is there anyway in Linux that can achieve atomic increment/decrement for an integer variable without being interrupted? It means that the thread should not chance for other thread to run until theincrement/decrement is completed.
View 11 Replies View RelatedAccording to [URL], gcc 4.3 supports atomic built-in function "GCC can now use load-linked, store-conditional and sync instructions to implement atomic built-in functions such as __sync_fetch_and_add" However, I am still using gcc 3.4 on my Redhat EL4. How do I get this built-in function installed?
View 2 Replies View RelatedI have this hdd and another with XP in it but when ever I chnage to UBuntu, the clock goes out of whack and, makes me manually change it whereas in my XP I have an atomic clock installed that I just click on 'Ping' and she's right. I've looked at heaps of downloads for similar on here but, I haven't found a free one other than a trial type that I'm not interested in, that works so, why is Linux so difficult in this regard? I will accept all the help I can get on here because I like the thought of being able to get away from Microsoft.
View 2 Replies View RelatedIntroduction : We have a C++ application in RHEL 5.4 platform. We are using TCP/IP socket programming as well to send and receive some sort of messages. We are using socket write and read command for this purpose and we are getting some run-time write issues in between. By doing various debugging and strace operations, we came to the conclusion that issue happens in some write attempts as follows.
Detailed Description : In the simplest case, consider I have a server and a client. Server writes some messages using write command and client is supposed to read the same data.Major code snippets in Server side is as follows [It is not feasible to extract the actual files and application codes as a whole, below are just the major commands used in server side]:
sockfd = socket(AF_INET, SOCK_STREAM, 0);
int reuse=1;
setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,& reuse, sizeof(reuse));
[code]....
While attempting to install 7.7 on i7 Samsung notebook, iwlwifi and rtl_nic files cannot be found on usb or sdc (have no floppy to try) Added the missing files to iso and burned new disc which would not boot.
View 1 Replies View RelatedAfter upgrading from 9.10 to 10.40.. My Cheese webcam doesn't work anymore. It says: No Camera Found!
And also one important thing is missing.. (I don't know how to say that).. "ALWAYS ON TOP"
How do i get back that?
I just had to do a reinstall of 11.3 when plasma refused to run. Now I'm noticing that applications are missing from (pacman) repo, but when I browse the repo with firefox, the rpms are there, they're just not being found by a yast search... Both mplayer and kdelnive are not found by yast. There are probably others...
View 5 Replies View RelatedI had installed koha 3.0.0 successfully.I am able to import data by using Marc Editor but i am not able to edit the data of ITEMSit shows the following errorThe following fatal error has occurred:found MARCXML element datafield, but the <record> wrapper is missing at /usr/lib/perl5/site_perl/5.12.3/MARC/File/XML.pm line 452ApacheServer version: Apache/2.2.17 (Linux/SUSE) Server built: 2010-10-21 14:13:51.000000000 +0000
Koha3.00.00.107Koha DB3.0000107MySQLmysql Ver 14.14 Distrib 5.1.53, for suse-linux-gnu (i686) using readline 6.1OSLinux koha-test 2.6.37.1-1.2-desktop #1 SMP PREEMPT 2011-02-21 10:34:10 +0100 i686 i686 i386 GNU/Linux
Perl5.012003Or
I have created a folder including some html link pages in /test/htlink . Now I want to create a soft link of that folder as htlink -> /test/htlink in /var/www/html . Now when I m browsing the folder , its erroring (404 Not Found) folder is not found on the server . I have given 777 permission on every file-folder in /test . No firewall & no SELINUX .
*** I want to browse the folder ***
using squeeze and trying to install asterisk on it. after entering the ./configure command this error appears configure: error: *** termcap support not found (on modern systems, this typically means the ncurses development package is missing) i've tried to find the soultion in google, but i couldn't.
View 1 Replies View RelatedI'm usin Ubuntu 9.10 and installed it a couple of months ago. I was trying to figure out how to use Synaptic to fix some dependancy errors I was getting, and set it to remove a certain package. It said it had to remove other packages as well to do this, well that ended up being Gnome and a whole bunch of other stuff. Silly me.So I was alright without having Gnome and went back to writing simple c++ from this book. I wrote a program to output a range of numbers and ran it but had written it wrong, so it would have ran on for hours. So I just killed the power and tried to start the comp again.
This time after the Dell boot screen it would tell me my system battery was low and strike F1 to continue or F2 to enter setup. Hit F1 and Im told that a file wasnt found and then it goes to the Ubuntu loading screen (The logo and some dots underneath) and then a black screen. Nothing else.I figured I needed to reintall and dont have any CDs so tried to make a live CD and this time when I try to boot from USB device get a "Missing Operating System" error.Its set to boot from USB device before harddrive. Need to know what to do to install again/recover old install.
I installed debian 4.0 (etch) on an old computer with some pickled graphics card in it, and then I upgraded the computer to one with slightly newer hardware only without the graphics card (the new one used on board graphics). I moved the hard drive from the old one to the new one but when I booted it up it failed to start the X-server and I got some errors listed for "device not found" and "no screens found".
I tried using "dpkg-reconfigure xserver-xorg" however I can't seem to find a working configuration. It seems pretty silly that when installing debian it can detect all this automatically with no problems but when it comes to changing some hardware around you are left in the dark with a complicated re-configuration process. Is there not some way to automate this? I'd rather not have to re-install everything
Having a problem on all of my Ubuntu machines when i goto this address: [URL]... i get a "server not found Firefox cant find the server [URL]... this is only happening on Linux i have a dual boot on an epc with vista and it loads the site. normally i wouldn't even care but my girlfriend will be taking on line classes here and i need to get this to load.
View 5 Replies View RelatedI am trying to solve a problem where Apache stats aren't displaying correctly in Munin. I've ran through quite a bit of checks and tests regarding Munin setup, but I think my issue is related to Apache, but my skill set there is lacking.
first, system info:
monitored server:
CentOS 5.3 2.6.18-128.1.1.el5
[code]....
I have a Debian mail server running Postfix, Amavisd-new, Clamav, & Spamassassin. I noticed when I started all the daemons, the mail.log file had some missing decoders which I assume Clamav can't scrub.Was there a missing package for resolving what's causing this notifications in the logs?
View 3 Replies View RelatedI am missing mysql from postconf for my centos server and I cant seem to enable it no matter what I try, does anybody know how to enable it?
Code:
[root@server ~]# postconf -m
btree
cidr
environ
[Code].....
just some time ago, my /usr partition's used space is started to increase rapidly, and currently it reached 17.5GB. We put /usr as a separate partition (/dev/sda2)
So when we do "df" this is the result:
Code:
#df
...
/dev/sda2 20315844 17612628 1654576 92% /usr
...
But what makes me puzzled is if I do "du", I only get 4.3GB instead of 20GB as "df" reported.
Code:
# du -csh /usr
4.3G /usr
4.3G total
So I'm missing approx 13GB here. My question is:where does my 13GB missing?
I installed Gmote 2.0 yesterday and it worked like a charm the first time and I could use most of it's features. But then after restarting the computer, I can not get my phone to find the server running on my computer anymore. I have tried whatever that came to my mind but it has not been successful.The first time, it just found it without any delays, but seems to be unable to do that now.
View 1 Replies View RelatedIs it possible to do a 301 redirect for all file not found on a whole server?
or at least a specific 404 document for the whole server instead of setting it up for each domain/user.
I am using CENTOS 5.6 x86_64
I have made linux raid array, named it md1 and it can be found under /dev/md1. I have created single partition (whole disk) of type LVM (8e) and it can be found under /dev/md1/md1p1.
When I run: pvcreate /dev/md1/md1p1
I get this message: Device /dev/md1/md1p1 not found (or ignored by filtering).
But if I run pvcreate /dev/md1
Everything went OK. I can create volume group and logical groups after that.
I haven't found anything specifically on net, except that partition for LVM to work should be of type 8e. Does this doesn't have to be true when we use whole disk as a VG? Should I expect any problems since this is going to be iSCSI target disk?
i am geting following error when i use make
make: -F.: Command not found
HBHB****
**** The configure script must be executed before running 'make'.
**** Please run "./configure".
****
make: *** [makeopts] Error 1
I have installed apache 2.2 from source and it works prefectly.
I compiled and installed php 5.2 but php pages resolve to page not found.
I checked the logs but did not find anything also apache has loaded the php5 module successfully.
Below is the apache configuration
[URL]
I downloaded the most recent version of debian and isntalled it. Everything went really well there. Until i issued free -m on the box. It would appear that the server is missing about 300mb of ram which is okay for i figured perhaps the video card / sound was taking that amount of ram for it'self. it was not until i installed Xen and I found a bigger problem with memory and my system. for what ever reason when I attempt to create a domU with 512mb of ram, i need to add 19MB more ram so that when i issue free -m from within the domU it will show a total of 512. worse yet is that when i raise the total up to 1024 for 1gb or domU ram, i need to addd 28mb or ram. and add 28mb of ram PER GB i wish to add to the domU.
View 1 Replies View RelatedI am somewhat new to linux, and fedora especially, I'm currently trying to get a linux based active directory server build in my home. I've tried using samba, dhcpd and the bind9 service but it wasn't wanting to work, so I did some searching and found 389ds on the fedora projects page. Now I'm having issues setting up the directory here's the log.
Code:
[11/05/29:10:37:47] - [Setup] Info This program will set up the 389 Directory and Administration Servers.
It is recommended that you have "root" privilege to set up the software.
Tips for using this program:
- Press "Enter" to choose the default and go to the next screen
- Type "Control-B" then "Enter" to go back to the previous screen
- Type "Control-C" to cancel the setup program
[11/05/29:10:37:47] - [Setup] Info Would you like to continue with set up?
[11/05/29:10:37:49] - [Setup] Info yes .....
[11/05/29:10:37:50] - [Setup] Info Your system has been scanned for potential problems, missing patches, etc. The following output is a report of the items found that need to be addressed before running this software in a production environment .....
I'm having issues getting apache to respond to requests outside of my local LAN. If I goto my server [URL].. it says connecting... but never finishes and returns anything. I'm using Ubuntu Server 10.10.
a) The DNS is working fine. It's pointed to my cable modem's IP and ping responds fine.
b) The apache server is setup and is working locally. In fact, if I use w3m and goto [URL]..I reach the test page perfectly. I can't figure out where the missing piece is to close this gap. Here are some config files to illustrate my setup:
[Code]...