This is almost certainly not the IO scheduler's problem. IO scheduling priorities are orthogonal to CPU scheduling priorities.
What you are likely running into is the dirty_ratio limits. In Linux, there is a memory threshold for "dirty memory" (memory that is destined to be written out to disk), that once crossed, will cause symptoms like you've described. The dirty_ratio values can be tuned via/proc, but beware that the kernel will internally add its own heuristics to the values you've plugged in.
When the threshold is crossed, in an attempt to "slow down the dirtiers", the Linux kernel will penalized (in rate-limited fashion) any and every task on the system that tries to allocate a page. This allocation may be in response to userland needing a new page, but it can also occur if the kernel is allocating memory for internal data structures in response to a system call the process did. When this happens, the kernel will force that allocating thread (again, rate-limited) to take part in the flushing process, under the (misguided) assumption that whoever is allocating a lot of memory is the same thread that is dirtying a lot of memory.
There are a couple ways to work around this problem (which is very typical when copying large amounts of data). For one, the copying process can be fixed to rate limit itself, and to synchronously flush data at some reasonable interval. Another way that a system administrator can manage this sort of task (if automated of course) is to use Linux's support for memory controllers which essentially isolates the memory subsystem performance between tasks. Unfortunately, it's support is still incomplete and I don't know of any popular distributions that automate this cgroup subsystem's use.
Either way, it is very unlikely to be the IO scheduler.
So to be correct, one should never test vs. 0, but rather vs. NULL.
Bzzt.
The language defines the null pointer constant to be zero, whether or not the underlying hardware uses all-zeroes. There is nothing wrong with testing against 0.
I wonder if Sun (who helped fund SCO's attack on Linux) has worked this out with SCO in some way that we'll only understand when the license comes out.
How did Sun help fund SCO? Please stop spreading this fud.
If you are referring to the way Sun pays SCO for SysV licensing, then in that same regard, IBM is funding the lawsuit against themself.
Both Red Hat and SuSE have been backporting fixes into older kernel versions and shipping 'older' versions of kernels is primarily due to stability requirements.
Distributions elect to use a given kernel version every once in a while. By not keeping up to date with the latest kernel.org tree, they gain the advantage that their codebase is much slower moving and they are less likely to have new bugs introduced from outside sources. Doing so also gives them the ability to accrue intimate knowledge of the inner workings of that specific kernel revision.
As distributions support a kernel, new bugs, vulnerabilities, hardware incompatibilities, and scalability issues arise. By selectively culling those single bits and pieces and patching their supported kernel, they are able to easily test the fixes without the larger risk of regressing in other areas.
At first, this practice may appear to make the distributions look 'unfriendly' towards the opensource development nature of the Linux kernel, however this is far from the truth. As issues arise in the distro-supported kernel, fixes are also created which are later pushed upstream to the Linux kernel proper (as long as they aren't considered gross hacks that is).
In essence, distributions settling on supporting specific kernel versions and patching them is very much in the open source spirit. OSS has the advantage that you may use any code drop you want, and if you fix something, the neighborly thing to do is to share the fix (which under certain license is enforced by law under some conditions).
Usually you can buy tens of thousands of images in clipart packs. Whoever posted that page on your site was lucky enough to come across two individuals that used the same one..
Re:I always thought is was in P
on
Real DRM
·
· Score: 2
Note on Java Support. The Operating System Components may contain support for programs written in Java. Java technology is not fault tolerant and is not designed, manufactured, or intended for use or resale as on-line control equipment in hazardous environments requiring fail-safe performance, such as in the operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life support machines, or weapons systems, in which the failure of Java technology could lead directly to death, personal injury, or severe physical or environmental damage.
What does this say about microsoft's views towards java technologies?
I've been using HP calculators since I was in grade 5. I remember the first day I received my trusty old 32SII. It was awkward at first, but RPN grew on me very fast. I continued to use this calculater, learning every function for it that I could. I used to laugh at my classmates for not even being able to add 1 + 2 on my calculater. It allowed me to be both pretentious and productive at the same time. It gave me a new unconventional way to look at the problems at hand.
Come university, I went out and splurged for my 48GX. Although I have yet to take the time to learn all of this beast-of-a-calculater's functionality, I know that if I did I would be even more productive. HP calculators are truly ingenious tools.
One thing I must say though is that I don't think it's fair that some educational institutions *make* students buy other more conventional calculaters. Specially in the fields and engineering and computer science. Students miss out by using the old-fashioned calculator, eg: the TI-8[69?]. Students learn and become dependent on their calculaters as they don't ever learn different ways of attacking the given problem. Blame the schools for not letting their students use a real calculater.
It's kinda ironic that you mention Stockwell (aka 'Doris') Day seeing as my 24-hour/american reference came from the same guy that pushed for Day to change his name. Stockwell and the 'Alliance' party of Canada were pushing for allowing a referendum with 350,000 votes (less than 3% of Canada's voting population..) The clip where the Doris Day bit came about is available for your plesure at:
That SNO is the Sudbury Neutrino Observatory and that Sudbury Ontario is not even close to Kingston Ontario. The confusion comes about from the fact that much of the research being done at SNO is being done by professors from Queens University, located in Kingston.
What about digitally masterful theives? I don't want to allow some punk riding down the street to know exactly what I have in my house!.. If this were EVER to be made, then I'd be the first to push for a blocker technology that would stop anyone from ever being able to determine what I had. I'd make it into a keychain on top of that so that I'd be query-safe from anyone everywhere I went. Just a thought.
This man doesn't know what he's talking about!!! As far as the 'free' concept goes, he's talking out of his ass.
On a side note: I have done a bit of research with regard Microsoft's.Net framework. I'm wondering if any company or individuals have taken it upon themselves to play catch-up with Microsoft and adopt.Net for the open source platforms. I understand that the technologies.Net has to offer are equivilent to what we already have (SOAP, Java, Corba,...), but I believe the adoption can only help the community as a whole... If I had the time and skills to tackle such a thing, I'd call it.Nix:)
Ya, I noticed that nobody has done anything similar for the sorenson codec.
Support for the Quicktime file format IS available, and if someone were willing to tie in the quicktime/windows libraries, then we'd finally be able to watch those damned superbowl commercials online:\
I remember playing MOO when I was really young. Me and my friend would play it all day and all night. We'd have a sleep over and pretend to go to sleep, and then when his parents were in bed, we'd sneak into the basement computer room. We were really scared of getting caught, so we'd crawl out the window and go outside if we had to pee.
We would spend so many countless hours playing that game, I'm afraid to pick up a copy of MOO3 when it comes out!
Slashdot Mirror
This is almost certainly not the IO scheduler's problem. IO scheduling priorities are orthogonal to CPU scheduling priorities.
What you are likely running into is the dirty_ratio limits. In Linux, there is a memory threshold for "dirty memory" (memory that is destined to be written out to disk), that once crossed, will cause symptoms like you've described. The dirty_ratio values can be tuned via /proc, but beware that the kernel will internally add its own heuristics to the values you've plugged in.
When the threshold is crossed, in an attempt to "slow down the dirtiers", the Linux kernel will penalized (in rate-limited fashion) any and every task on the system that tries to allocate a page. This allocation may be in response to userland needing a new page, but it can also occur if the kernel is allocating memory for internal data structures in response to a system call the process did. When this happens, the kernel will force that allocating thread (again, rate-limited) to take part in the flushing process, under the (misguided) assumption that whoever is allocating a lot of memory is the same thread that is dirtying a lot of memory.
There are a couple ways to work around this problem (which is very typical when copying large amounts of data). For one, the copying process can be fixed to rate limit itself, and to synchronously flush data at some reasonable interval. Another way that a system administrator can manage this sort of task (if automated of course) is to use Linux's support for memory controllers which essentially isolates the memory subsystem performance between tasks. Unfortunately, it's support is still incomplete and I don't know of any popular distributions that automate this cgroup subsystem's use.
Either way, it is very unlikely to be the IO scheduler.
Bzzt.
The language defines the null pointer constant to be zero, whether or not the underlying hardware uses all-zeroes. There is nothing wrong with testing against 0.
Please RTFFAQ
How did Sun help fund SCO? Please stop spreading this fud.
If you are referring to the way Sun pays SCO for SysV licensing, then in that same regard, IBM is funding the lawsuit against themself.
Both Red Hat and SuSE have been backporting fixes into older kernel versions and shipping 'older' versions of kernels is primarily due to stability requirements.
Distributions elect to use a given kernel version every once in a while. By not keeping up to date with the latest kernel.org tree, they gain the advantage that their codebase is much slower moving and they are less likely to have new bugs introduced from outside sources. Doing so also gives them the ability to accrue intimate knowledge of the inner workings of that specific kernel revision.
As distributions support a kernel, new bugs, vulnerabilities, hardware incompatibilities, and scalability issues arise. By selectively culling those single bits and pieces and patching their supported kernel, they are able to easily test the fixes without the larger risk of regressing in other areas.
At first, this practice may appear to make the distributions look 'unfriendly' towards the opensource development nature of the Linux kernel, however this is far from the truth. As issues arise in the distro-supported kernel, fixes are also created which are later pushed upstream to the Linux kernel proper (as long as they aren't considered gross hacks that is).
In essence, distributions settling on supporting specific kernel versions and patching them is very much in the open source spirit. OSS has the advantage that you may use any code drop you want, and if you fix something, the neighborly thing to do is to share the fix (which under certain license is enforced by law under some conditions).
Automount and autofs trigger filesystem mounts on directory traversals, not on media insertion.
Maybe you were thinking about vold or some other similar project.
And sending your password in cleartext over the intra/internet is more secure?
Usually you can buy tens of thousands of images in clipart packs. Whoever posted that page on your site was lucky enough to come across two individuals that used the same one..
ln -sf /tmp/foo.au /dev/dsp
I hate replying to my own posts, but upon further inspection, I realized that sqrt(n) > log(n)^12 for large n.
Yet, sqrt(n) is still polynomial time.
Uhh..
Pardon my french, but isn't sqrt(n) is better than log(n)^12?
These guys have been working on kernel patches, acl tools and a posix compliant acl library for some time and it works pretty well :)
http://sourceforge.net/projects/linux-acl/
Note on Java Support. The Operating System Components may contain support for programs written in Java. Java technology is not fault tolerant and is not designed, manufactured, or intended for use or resale as on-line control equipment in hazardous environments requiring fail-safe performance, such as in the operation of nuclear facilities, aircraft navigation or communication systems, air traffic control, direct life support machines, or weapons systems, in which the failure of Java technology could lead directly to death, personal injury, or severe physical or environmental damage.
What does this say about microsoft's views towards java technologies?
wow.. I wasn't expecting the Spanish inquisition!
I've been using HP calculators since I was in grade 5. I remember the first day I received my trusty old 32SII. It was awkward at first, but RPN grew on me very fast. I continued to use this calculater, learning every function for it that I could. I used to laugh at my classmates for not even being able to add 1 + 2 on my calculater. It allowed me to be both pretentious and productive at the same time. It gave me a new unconventional way to look at the problems at hand.
Come university, I went out and splurged for my 48GX. Although I have yet to take the time to learn all of this beast-of-a-calculater's functionality, I know that if I did I would be even more productive. HP calculators are truly ingenious tools.
One thing I must say though is that I don't think it's fair that some educational institutions *make* students buy other more conventional calculaters. Specially in the fields and engineering and computer science. Students miss out by using the old-fashioned calculator, eg: the TI-8[69?]. Students learn and become dependent on their calculaters as they don't ever learn different ways of attacking the given problem. Blame the schools for not letting their students use a real calculater.
And what about us canadians? Can we jump into such a class action suit as well?
Then by your logic, Mexicans are Americans too!
http://www.22minutes.com/realwrapper.php?target=do ris_day.rm
Do I really need to give a reason?
Ain't it awful when you forget to check 'Post Anonymously'?
That SNO is the Sudbury Neutrino Observatory and that Sudbury Ontario is not even close to Kingston Ontario. The confusion comes about from the fact that much of the research being done at SNO is being done by professors from Queens University, located in Kingston.
What about digitally masterful theives? I don't want to allow some punk riding down the street to know exactly what I have in my house!.. If this were EVER to be made, then I'd be the first to push for a blocker technology that would stop anyone from ever being able to determine what I had. I'd make it into a keychain on top of that so that I'd be query-safe from anyone everywhere I went. Just a thought.
On a side note: I have done a bit of research with regard Microsoft's .Net framework. I'm wondering if any company or individuals have taken it upon themselves to play catch-up with Microsoft and adopt .Net for the open source platforms. I understand that the technologies .Net has to offer are equivilent to what we already have (SOAP, Java, Corba, ...), but I believe the adoption can only help the community as a whole... If I had the time and skills to tackle such a thing, I'd call it .Nix :)
You guys realize that you'll be seeing ALOT more of this now that George 'double ya' Bush got elected.. tsk tsk
Support for the Quicktime file format IS available, and if someone were willing to tie in the quicktime/windows libraries, then we'd finally be able to watch those damned superbowl commercials online :\
We would spend so many countless hours playing that game, I'm afraid to pick up a copy of MOO3 when it comes out!