if I remember correctly, myfishbear has stated that 'noop' is the best scheduler, but I was looking at speedscriptv3, and it says
I assume that setting 'noop' in setcpu would override that, but I'm wondering which really is 'best'?#sets I/O scheduler to SIO, considered best
I'm running eclipse 1.2.6 with hotplugx and noop, and my battery life still isn't very good (I get about 10 hours with light usage). I'm wondering what effect speedscript has on the battery. I see at least one place that mentions saving the battery, but I wonder if the overall effect is to speed things up at the expense of battery life...
Argh... when using the lapdock watching embedded flash videos is choppy. I switch to full screen it stops. Hmmm...
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Before I did a fresh wipe and install the lap dock with ICS browser+ default desktop pulls up the mobile YouTube site. I miss HD... anyone else have this issue? Idk why after a fresh install this started happening. It seems its only the ICS+ plus browser.
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Last edited by Usuallyfaded; 09-20-2012 at 12:12 PM.
Inserts all the incoming I/O requests to a First In First Out queue and implements request merging. Best used with storage devices that does not depend on mechanical movement to access data (yes, like our flash drives). Advantage here is that flash drives does not require reordering of multiple I/O requests unlike in normal hard drives.
- Serves I/O requests with least number of cpu cycles. (Battery friendly?)
- Best for flash drives since there is no seeking penalty.
- Good throughput on db systems.
- Reduction in number of cpu cycles used is proportional to drop in performance.
Goal is to minimize I/O latency or starvation of a request. The same is achieved by round robin policy to be fair among multiple I/O requests. Five queues are aggressively used to reorder incoming requests.
- Nearly a real time scheduler.
- Excels in reducing latency of any given single I/O.
- Best scheduler for database access and queries.
- Bandwidth requirement of a process - what percentage of CPU it needs, is easily calculated.
- Like noop, a good scheduler for solid state/flash drives.
- When system is overloaded, set of processes that may miss deadline is largely unpredictable.
Completely Fair Queuing scheduler maintains a scalable per-process I/O queue and attempts to distribute the available I/O bandwidth equally among all I/O requests. Each per-process queue contains synchronous requests from processes. Time slice allocated for each queue depends on the priority of the 'parent' process. V2 of CFQ has some fixes which solves process' i/o starvation and some small backward seeks in the hope of improving responsiveness.
- Considered to deliver a balanced i/o performance.
- Easiest to tune.
- Excels on multiprocessor systems.
- Best database system performance after deadline.
- Some users report media scanning takes longest to complete using CFQ. This could be because of the property that since the bandwidth is equally distributed to all i/o operations during boot-up, media scanning is not given any special priority.
- Jitter (worst-case-delay) exhibited can sometimes be high, because of the number of tasks competing for the disk.
Simple I/O scheduler aims to keep minimum overhead to achieve low latency to serve I/O requests. No priority quesues concepts, but only basic merging. Sio is a mix between noop & deadline. No reordering or sorting of requests.
- Simple, so reliable.
- Minimized starvation of requests.
- Slow random-read speeds on flash drives, compared to other schedulers.
- Sequential-read speeds on flash drives also not so good.