Ubuntu Multimedia :: Optimizing 10.04 For Hi Fi Purpose ?
Aug 24, 2010
I have just bought a digital-to-analog converter, this one to be exact, along with an amplificator and two speakers. I'd like to get the most of my Ubuntu, a good sound (what player can I use ?) and to know wether I need to do some extra changes in the kernel (OSS / PulseAudio / ALSA ?) or not.
I wonder if my converter will be detected when i plug it in, and if any sound from my computer will be leaded to it automatically ? (I'll have the converter tomorrow). I believe its purpose is to replace the sound card, to provide a greater, pure sound. The converter is linked by USB by the way.
I have a friend who is using Ubuntu 10.10 Netbook Edition on their netbook and well they love it. However, I notice that at times (if not all the time) their internet is ridiculously slow. Yes, it's a 1 Mbps download connection, but I still think it's a little slow and at times I can't even get it to load a website. I'm thinking if I adjusted the MTU within Ubuntu, it might improve, if even only slightly. I believe the router is set to 1490 or 1500, I haven't really looked yet.
I am working on optimizing the iptables. I came across some way of optimizing the rules by removing the redundant rules and merging the rules . Is there any other way to increase the optimization of iptables ?The network that we applied the iptables is a simple LAN network. (College Network)
I would like to ask how can I optimize apache2 load on my dedicated server. I am hosting Facebook applications on it, but most users will get a Timed Out message when they try to access it. I was tinkering with MaxClients directive in apache2 config, and it got better, but still it's not best. Programmers are trying their best to optimize the applications at their side, but I am afraid this is an server issue.
I wrote a little Bash script which accepts two values -- sender address and recipient address -- and finds any instances of mail sent from sender to recipient in /var/log/maillog. The script works fine, but it seems to be very inefficient. I'm just wondering how I can optimize it.
Code:
Example:
Code:
Again, it seems to work fine, but the script greps through /var/log/maillog three times -- first to find the sender; second to see if it's also going to the desired recipient; finally to view all instances of the message ID in the logs. This seems redundant and inefficient.
I'm trying to solve this problem, but always get Time limit exceeded. I've tried my best but still can't get under time limit. Could you please give me some hint about it?
I am running Ferdora 12 (constantine) 64 with Intel Xeon 3.2GHz processor + 12GB Ram. I am running this machine specifically for number chunching applications but it isnt running as fast as i thought it would! Are there any tips to optimizing the speed of processors in fedora?
I recently purchased a Western Digital 1TB USB hard drive to use for general data storage. I had thought about repartitioning it into 8 - 10 individual drives (most Linux users will doubtless understand the arguments for and against this) and reformatting them with another filesystem, probably ext2.
The unit actually consists of two 500GB drives that are presented by the internal controller as a single 1TB drive, and are formatted with the old HPFS/NTFS filesystem, so I'm a bit cautious about the possibility of my original plan confusing the drive's controller. Does anyone have any experience with these large drives, any thoughts about repartitioning/reformatting, and relevant criteria for optimizing their use?
Where can I find comprehensive information on optimizing Linux? I keep searching online but seem to get only to performance monitoring. I don't want to run a lighter version of Linux or upgrade my hardware! Just want to get my current distro and future ones I might install to run at its best.
I tried to summarize the this as best as possible in the title. I am writing an initial value problem solver in the most general way possible. I start with an arbitrary number of initial values at arbitrary locations (inside a boundary.) The first part of my program creates a mesh/grid (I am not sure which is the correct nuance), with N points total, that contains all the initial values. My goal is to optimize the mesh such that the spacing is as uniform as possible. My solver seems to work half decently (it needs some more obscure debugging that is not relevant here.)
I am starting with one dimension. I intend to generalize the algorithm to an arbitrary number of dimensions once I get it working consistently. I am writing my code in fortran, but feel free to reply with pseudocode or the language of your choice.Allow me to elaborate with an example:Say I am working on a closed interval [1,10]
I store my mesh/grid points in an array called coord. Say I want 10 points total in my mesh/grid.
N=10 coord(10)
Remember, all this is arbitrary--except the variable names of course. The algorithm should set coord to {1,2,3,4,5,6,7,8,9,10} Now for a less trivial example:
num_ivc=3 known(num_ivc)=[xmin,5.5,xmax or just num_ivc=1 known(num_ivc)=[5.5]
Now, would you have 5 evenly spaced points on the interval [1, 5.5] and 5 evenly spaced points on the interval (5.5, 10]? But there is more space between 1 and 5.5 than between 5.5 and 10. So would you have 6 points on [1, 5.5] followed by 4 on (5.5 to 10]. The key is to minimize the difference in spacing.I have been working on this for 2 days straight and I can assure you it is a lot trickier than it sounds. I have written code that
only works if N is large only works if N is small only works if it the known points are close together
[code]....
So as you can see, I have coded the gamut of almost-solutions. I cannot figure out a way to get it to perform equally well in all possible scenarios (that is, create the optimum spacing.)
On my bare metal server, I get about 130MB/s read from a software RAID 10 array, but when reading the same file from a VM via NFS over the VirtIO interface,I only get about 40MB/s.
Furthermore, the process for the VM uses >180% CPU on the host, and ~40%, and the 5 min average is ~1.5 on the host and guest. I have dual E5620's so I'm disappointed that the transfer is so slow, as I was expecting at least 90MB/s.
I'm new to being a sysadmin, so if anyone has some tips I can use to increase the transfer rate, and possibility reduce the CPU load as well I'd appreciate it. I'm assuming that 130MB/s is the max speed of two 7.2k HDDs, but if there's any way I can squeeze any more out that would be great too.
System specs:
2x Intel Xeon E5620s @ 2.40Ghz 8GB of RAM @ 1066Mhz 4x 1TB Western Digital Black HDDs in RAID10
I have a dual boot on a netbook with windows and fedora13. When I am on my fedora boot and I try to watch streaming video it comes through in waves or not at all. I do not have the same problems on the alternate boot. There are other performance comparisons where the windows boot runs smoother and faster. Is there any work I can do in order to optimise my fedora boot in this capacity?
So I've come across several tips to optimize battery life on Linux. [URLs]. In addition to undervolting, I would like to underclock. Is there a way to control CPU speed outside of the BIOS via some software control in Linux... or some sort of boot manager? I would like to boot to linux using underclocked speeds and have Windows running full blast. Is there a way to run Linux completely in RAM? I have read that saves on power consumption from the hard drive.
I just removed mysql-client after installing php5-mysql and my php is connecting to my remote server fine. What is the purpose of mysql-client? Is it a direct API for external servers?
[URL]
So it's basically /usr/bin/mysql that allows connection to external servers
today when i tried to login into another host my network using ssh it gave me an error saying that the remote host RSA key has changed and i should remove the file .ssh/<idon't rememeber> from my home directory for loggin in and it also gave me the warning that somebody is doing something nasty, As far as i remember we only reinstalled the system that ip, but then after deleting the file .ssh when i put the root password to that system it says bad password, What is an RSA key and what is its purpose under what circumstances is the RSA key gets changed, does it get changed after reinstallation what can do nasty that can change the RSA key
I have a folder that may contain text documents, pictures, MP3s, video clips, all sorts of stuff. Supposing that, within reason, I'm not too bothered how long it takes to compress and uncompress them. And suppose I don't care if it's free or open source (well, has to be free as in beer). What's the best compression format/algorithm (whatever it is that I install in Synaptic and choose from the drop down menu in the compression tool) I should use?
The last time I wrote code for anything was about 15 years ago using Turbo Pascal. I would like to get back into it, most likely to create some mobile apps or enhance web sites. What is the best general purpose language to learn? And what is a good method for learning, preferably free?
I want to create a general switch that I can use to send a signal to my ubuntu server when it is activated/deactivated. Here's an example: I want to know when a certain door is open, so I can have a switch closed when the door is closed and opened when the door is opened. When opened or closed, the computer will receive a signal and I can have some software intercept this signal and process it to my liking (i.e. ring a bell/text message me/email me/etc).
I know I will have to create a simple driver, software to make use of this signal, etc... I am willing to do whatever it takes to make it happen. I'm just wondering if anyone can point me in the right direction as far as which interface I should use to communicate with my server (i.e. usb, serial), which references I should read, and any personal experience you have with something like this...
I am in the process of creating a USB multi boot with a variety of utilities for working on pc's as well as multiple distributions for testing via live use and for installation. From what I've found YUMI is the tool to use to create this. Is that right or does anyone have a better tool to use? As long as YUMI is the best tool, does anyone have any best practices to pass on? I'm thinking of relating to casper-rw, preventing any fragmentation issues and etc. Anything else to be thinking of as I create this would be very much welcomed. I'm planning to start with a 16GB stick but I'm curious about how much space others are finding they need. I don't know if 16GB is way high or low.Anyway, what all can you pass on to me and others in the forums about planning for and using a multi boot usb.
I've always been confused about this issue of boot partitions. In the past when I install linux I usually have 2-3 partitions.
1. Main OS partition mounted on / 2. Storage partition mounted on /home 3. Swap partition
Why and when would I need to have a boot partition? Even if I dual boot two OSs, I just make one more partition for that other OS. So what's the purpose of a boot partition?
Can you explain me what is purpose of shebang in scripts? I have noticed that my scripts will run without shebang. i.e. When i save my crontab file it says that scripts will be executed in i.e. /bin/sh shell. So, what is the point if I put #!/bin/ksh at the start of script?
I attempted to run various cron jobs as root - just general server make-tidy stuff. But if I edit the /etc/crontab file directly, these tasks don't get run. However, if I use crontab -e as root, these jobs appear to work. Any idea why this might be the case? Also, I understand that user cron jobs are stored in /var/spool/cron/<user> (including root). If this is the case, what's the purpose of the /etc/crontab file?
I'm wondering if anyone can give me some guidance, or point me to a relevant reference for setting up a single purpose ssh key.I have setup a single purpose key for rsync, where I have command="/path/to/rsync-secure" associated with the public key in .ssh/authorized_keys, and the rsync-script checks to make sure incoming commands begin with 'rsync --secure', What I would like to do is do something similar to allow sshfs access, and have the server path that can be mounted locked down to a particular location. Does anyone have any suggestions as to how this could be done?As an aside, I might also want to restrict the above rsync script to only allow synchronization to a particular path.
using these fetchmail and postfix for fetching mail and sending mail ...... Instead of using incoming and outgoing like smtp and pop3 in outlook , why we use fetchmail and postfix mail server in linux and forward this to local windows client Outlook ..
