OTBNR: Windows 7 User Mode Scheduler
Erik Funkenbusch
Off-Topic, But Not Really in the subject) and how it's just Vista with some
polish. Just as a bit of rebuttal, here's an interesting new feature of
Windows 7 that doesn't show up on the marketing copy.
The User Mode Scheduler
http://channel9.msdn.com/shows/Going+Deep/Dave-Probert-Inside-Windows-7-User-Mode-Scheduler-UMS/
This is part of the Windows 7 push to better deal with multi-core and
multi-processor scaling. It allows applications to better control their
threads to make better use of multiple cores.
No, this has nothing to do with Linux, but then neither do Roy's ramblings
about Vista and Windows 7. It's just a data point in the "Windows 7 is
just vista sp2" crap that Roy and others like to spread.
Sinister Midget
> People like Roy like to go on and on about Windows 7 (which is why I wrote
> Off-Topic, But Not Really in the subject) and how it's just Vista with some
> polish. Just as a bit of rebuttal, here's an interesting new feature of
> Windows 7 that doesn't show up on the marketing copy.
>
> The User Mode Scheduler
> http://channel9.msdn.com/shows/Going+Deep/Dave-Probert-Inside-Windows-7-User-Mode-Scheduler-UMS/
Let's see if it's there when they release.
> This is part of the Windows 7 push to better deal with multi-core and
> multi-processor scaling. It allows applications to better control their
> threads to make better use of multiple cores.
IOW this is something they left out of Vista because they were having
trouble with it and had enough bugs to push out the door already. Now
that a couple of years have passed, giving them more time to work on it,
they put it back in for possible release in ME III. And maybe it'll
even work this time.
But if it's not in the release, we'll know what happened.
> No, this has nothing to do with Linux, but then neither do Roy's ramblings
> about Vista and Windows 7. It's just a data point in the "Windows 7 is
> just vista sp2" crap that Roy and others like to spread.
Roy's "ramblings" about Vista 7 ME (aka ME III and Vista sp2) are
related in that MS is a dirty-dealing, crooked monopoly, who will stoop
to any level to undermine any threat they think exists, real or not.
Since they already named linux a threat, their actions are relevant.
However, you, being a troll in a linux group, are off-topic, whether
you're discussing topics that are normally on-topic or not.
--
Security is one of those funny things. You can talk about being "more"
secure, but there's no such thing. A vulnerability is a vulnerability, and
even one makes you just as insecure as anyone else. Security is a binary
condition, either you are or you aren't.
-- Erik Funkenbusch, Message-ID: <tn9sapuzcil3$.d...@funkenbusch.com>
DFS
> Roy's "ramblings" about Vista 7 ME (aka ME III and Vista sp2) are
> related in that MS is a dirty-dealing, crooked monopoly, who will
> stoop to any level to undermine any threat they think exists, real or
> not.
Signed, Gidget
I Make My Living With Microsoft Windows
Always Have, Always Will
But Don't Call Me A Moron Hypocrite
High Plains Thumper
> Erik Funkenbusch claimed:
>
>> People like Roy like to go on and on about Windows 7 (which
>> is why I wrote Off-Topic, But Not Really in the subject) and
>> how it's just Vista with some polish.
OTBNR? "OT" = off topic? "BNR" = Bengal Nagpur Railway?
Bladder Neck Resection? Branch for No Reason? (Ah, best one,
related to computing.)
There is considerable controversy over schedulers that are best
left for a technical discussion outside advocacy.
http://sources.redhat.com/ml/libc-alpha/2007-01/msg00111.html
From: "Kaz Kylheku" <kaz at zeugmasystems dot com>
Date: Tue, 30 Jan 2007 13:16:22 -0800
Subject: RE: [ANN] Userspace M-on-N threading model
implementation. Alpha release.
[quote]
Evgeniy Polyakov wrote:
> I described in details why and how M:N model better, and its
> drawbacks include all issues mentioned by Ulrich Drepper, but
> nevertheless its advantages are far too superiour than those
> which can be provided by 1:1 model.
M:N threading is an unnecessary performance hack that's needed by
people who are living in a C or C++ exile away from some language
that has lexical closures, generators or first-class
continuations. Not having these niceties, they resort to
emulating them with threads. The proper thing to do is to rewrite
the code to use state machines which can be driven by any
available thread. Or else, write yourself a source-to-source
transformer that will give C the lexical closure, generator, or
continuation features that you need to express the solution that way.
There is no need to retain any vestiges of a user space threading
implementation when you have the real thing.
Programs which appear to benefit from that model are badly
optimized or badly designed. A smartly written program uses an
available thread to do as much work as possible, until that
thread happens to block or its time slice burns up.
[/quote]
Linux scheduler was vastly improved in Image 2.6 from Image 2.4
http://www.ibm.com/developerworks/linux/library/l-scheduler/?ca=dgr-lnxw07LinuxScheduler
which includes better support for SMP systems, task preemption,
dynamic task prioritisation, SMP load balancing, etc.
[quote]
Table 1. Linux 2.6 scheduler functions
Function name - Function description
* schedule - The main scheduler function. Schedules the highest
priority task for execution.
* load_balance- Checks the CPU to see whether an imbalance
exists, and attempts to move tasks if not balanced.
* effective_prio - Returns the effective priority of a task
(based on the static priority, but includes any rewards or
penalties).
* recalc_task_prio - Determines a task's bonus or penalty based
on its idle time.
* source_load - Conservatively calculates the load of the source
CPU (from which a task could be migrated).
* target_load - Liberally calculates the load of a target CPU
(where a task has the potential to be migrated).
* migration_thread - High-priority system thread that migrates
tasks between CPUs.
[/quote]
But in reality, much of this hype is timed just right on the eve
of Windows 7, to astroturfing heights. A seeming explanation may
be found in:
http://www.groklaw.net/articlebasic.php?story=20071023002351958
or downloading Comes vs Microsoft lawsuit, Microsoft Evangelism
document, http://www.groklaw.net/pdf/Comes-3096.pdf
[quote]
In the Slog, Microsoft dukes it out with the competition. MSDN
and Platform marketing are the regular forces, exchanging blows
with the enemy mano a mano. Evangelism should avoid formal,
frontal assaults, instead focusing its efforts of hit-and-run
tactics.
In the Slog, the enemy will counter-attack, trying to subvert
your Tier A ISVs to their side, just as you should try to subvert
their ISVs to your side. New ISVs should be sought, and directed
to MSDN's one-to- many programs. Evangelism should constantly be
on the lookout for killer demos, hot young startups, major ISVs,
customer testimonials, enemy-alliance-busting defections and
other opportunities to demonstrate momentum for our technology.
If bugs are found in our technology, or missing features are
found to be critically important, then now is the time to
identify and fix them. Stay engaged with the technology
development team; ensure that you are a valuable resource for
them, not a hectoring pest.
[/quote]
--
HPT
Erik Funkenbusch
> Sinister Midget wrote:
>> Erik Funkenbusch claimed:
>>
>>> People like Roy like to go on and on about Windows 7 (which
>>> is why I wrote Off-Topic, But Not Really in the subject) and
>>> how it's just Vista with some polish.
>
> OTBNR? "OT" = off topic? "BNR" = Bengal Nagpur Railway?
> Bladder Neck Resection? Branch for No Reason? (Ah, best one,
> related to computing.)
Why don't you try reading. I posted what it means in the text you quote
above. Too stupid to read it?
Investigative Reporter Web server
Nice, that's real good of you.