| Kirjoittaja | Viesti | ||
     KimmoK |
Interactivity and Responsiveness In addition to just scaling up, another priority with the new release has been to make the system more responsive. This is useful not only for the general desktop user (who always likes to see things respond quickly), but also to more time-critical applications where absolute preciseness is required to achieve the desired effect. Despite these changes, Linux 2.6 will not be a "hard" Real Time OS, which has very strict requirements for absolutely ensuring that actions happen predictably, but the overall responsiveness improvements should appeal to all classes of Linux users. (That said, there are external projects which have unofficial patches to provide RTOS functionality. Those projects could conceivably be made official in the next major release.) One of the key improvements in Linux 2.6, is that the kernel is finally preemptible. In all previous versions of Linux, the kernel itself cannot be interrupted while it is processing. (On a system with multiple processors, this was true on a per-CPU basis.) Under Linux 2.6, the kernel now can be interrupted mid-task, so that other applications can continue to run even when something low-level and complicated is going on in the background. Of course, there are still times when the kernel cannot be interrupted in its processing. In reality, most users never saw these delays, which are rarely over small fractions of a second. Despite that, many users may notice an improvement in interactive performance with this feature enabled; things like user input will "feel" faster, even when the system is bogged down. Linux's Input/Output (I/O) subsystems has also undergone major changes to allow them to be more responsive under all sorts of workloads. These changes include a complete rewrite of the I/O scheduler, the code of the kernel that determines what processes get to read from devices and when. The newly rewritten layer is now better capable of ensuring that no processes get stuck waiting in line for too long, while still allowing for the older optimizations which made sure that reading data still happens in the most efficient way for the underlying hardware. On the application software side, another change that will help make Linux programs more responsive (if they use the feature) is support for new "futexes" (or "Fast User-Space Mutexes") Futexes are a way in which multiple processes or threads can serialize events so that they don't trample on each other (a "race condition"). Unlike the traditional mutex operations that most threading libraries support, this concept is partially kernel based (but only in the contention case) and it also supports setting priorities to allow applications or threads of higher priority access to the contested resource first. By allowing a program to prioritize waiting tasks, applications can be made to be more responsive in timing-critical areas. In addition to all of the above, there have been a number of other smaller changes which will improve interactivity and performance in many cases. These include more removals of the "Big Kernel Lock" (non-fine-grained locks which were used in the early days' of Linux's support for multiple processors), optimizations of filesystem readahead, writeback, and manipulating small files, and other similar changes. ((jos Hyperionin AOS4+A1 aikataulu lipsuu lisää, tuo tuonee lohtua A1 käyttäjille)) | ||
| Joanna |
 Vielä kun keksisivät jonkin X-windowinia paremmin pöytäkäyttöön sopivan speksin ja sitten tekisivät systeemin niin että sitä todella voisi sujuvasti konffata Gui.lla niin olisi jo pitkällä. | ||
| Pekka Nissinen |
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| KimmoK |
Ohessa lista jota voi huvittaa selata vaikkapa 20 sekuntia.... http://www.linux-m68k.org/Registry/Internet.html | ||
| itix |
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| miksuh |
Tosin mulla ei ole nyt ollu linuxia enää vähään aikaan. Linuxille ei nyt ole tilaa tola 10GB levyllä, eikä mediatoille muutenkaan ole linux ajureita. | ||
| miksuh |
Eli ei ihan ajantajsalla toi Heheh ja typona muka 10Mt levy :D | ||
| Teccrom |
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| JPQ |
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