Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Gorka Guardiola
On Fri, Oct 29, 2010 at 7:37 AM, Bruce Ellis bruce.el...@gmail.com wrote: No! Open on an exclusive file has the same races. No problems on I said I agree it is a problem. Yes, there is a race... Froggie? A lily-white duck come and swallowed him up,..

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
What you are saying is that the problem could be something like: - Tclunk (do not wait for response) - Topen (the file is exclusive) no, because what actually happens is closer to A: Topen ... queue request to *another process* to send Tclunk ... A: Topen

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
my froggie has been running for four years 24/7. if you haven't read the BLTJ then styx runs over the PCI ... 4 ixp1200s. asynch clunks. the only problem is it's 10 times quicker. the only server that i saw at the labs that had Rclunk semantics was pb's video magic which i i didn't need. nemo

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
i don't believe that is possible in my implementation. will check. brucee On Fri, Oct 29, 2010 at 8:01 PM, Charles Forsyth fors...@terzarima.net wrote: What you are saying is that the problem could be something like: - Tclunk (do not wait for response) - Topen (the file is exclusive) no,

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Gorka Guardiola
On Fri, Oct 29, 2010 at 11:01 AM, Charles Forsyth fors...@terzarima.net wrote: What you are saying is that the problem could be something like: - Tclunk (do not wait for response) - Topen (the file is exclusive) no, because what actually happens is closer to        A: Topen        ...        

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
right journal. i'll do some unusual tests and report on the results. wing-commander has to awake early to attend his mother's 80th birthday party. back to you on this one. brucee On Fri, Oct 29, 2010 at 8:45 PM, Gorka Guardiola pau...@gmail.com wrote: On Fri, Oct 29, 2010 at 11:01 AM, Charles

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 28 October 2010 21:18, Charles Forsyth fors...@terzarima.net wrote: the race is that there's nothing to say that the clunk completes before the process continues on to do something more, including some action that depends on the clunk completing, such as simply repeating the open. that

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Lucio De Re
On Fri, Oct 29, 2010 at 02:12:11PM +0100, roger peppe wrote: so this trick is unsafe in general, but might be ok sometimes. So is the answer to add semantics to Topen or add a Treopen that obviates the Tclunk? ++L

[9fans] What USB audio device are you using?

2010-10-29 Thread John Floren
Here's an open question to anyone using USB audio on Plan 9: What device are you using? How well does it work? I'm looking for something I can get on Amazon; my T22 has been silent long enough! John

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Eric Van Hensbergen
On Fri, Oct 29, 2010 at 4:01 AM, Charles Forsyth fors...@terzarima.net wrote: What you are saying is that the problem could be something like: - Tclunk (do not wait for response) - Topen (the file is exclusive) no, because what actually happens is closer to        A: Topen        ...        

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 29 October 2010 15:14, Eric Van Hensbergen eri...@gmail.com wrote: Just to make sure I understand things correctly, where does this mess things up with standard (as opposed to synthetic) file systems? i think that part of the problem is that plan 9 makes no distinction between standard and

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread erik quanstrom
i think that part of the problem is that plan 9 makes no distinction between standard and synthetic file systems. perhaps if there was, then optimisations like this could work a little less haphazardly. what's a reasonable definition of standard? - erik

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Eric Van Hensbergen
On Fri, Oct 29, 2010 at 10:21 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 15:14, Eric Van Hensbergen eri...@gmail.com wrote: Just to make sure I understand things correctly, where does this mess things up with standard (as opposed to synthetic) file systems? i think that part

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
things up with standard (as opposed to synthetic) file systems? why should a synthetic file system (actually they are all synthetic, i think) be considered not standard? i thought file systems were the common currency in the system.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
in practise, there is no race if the tree is being imported via plan9's exportfs(4) because it services clunk requests synchronously. there is indeed a race because another process is issuing the clunk(s), not the one that's doing the open(s).

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
Do you do completely asynch clunks or just the wait for the response?. it uses `completely' async clunks, which is why it can be broken. having the original process send the Tclunk and not wait for the Rclunk is different. i think it was mentioned last time this matter came up, and that's

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Eric Van Hensbergen
On Fri, Oct 29, 2010 at 10:49 AM, Charles Forsyth fors...@terzarima.net wrote: things up with standard (as opposed to synthetic) file systems? why should a synthetic file system (actually they are all synthetic, i think) be considered not standard? i thought file systems were the common

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
having the original process send the Tclunk and not wait for the Rclunk is different. ah. having thought about it, i see it's different only in the case of one process. it isn't different if you have several processes that are trying to co-operate in an allowed way: failing to let the issuing

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Venkatesh Srinivas
On Fri, Oct 29, 2010 at 5:01 AM, Charles Forsyth fors...@terzarima.netwrote: What you are saying is that the problem could be something like: - Tclunk (do not wait for response) - Topen (the file is exclusive) no, because what actually happens is closer to A: Topen ...

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
this discussion was more interesting in thev UNIX room. froggie hasn't hung up yet thru a serious thrashing this evening - and all the FSs are synthetic - it has no disk. as much as i like philosophizing that's not my way. brucee On Sat, Oct 30, 2010 at 2:50 AM, Eric Van Hensbergen

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 29 October 2010 17:01, Charles Forsyth fors...@terzarima.net wrote: Do you do completely asynch clunks or just the wait for the response?. it uses `completely' async clunks, which is why it can be broken. having the original process send the Tclunk and not wait for the Rclunk is different.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Venkatesh Srinivas
On Fri, Oct 29, 2010 at 12:01 PM, Charles Forsyth fors...@terzarima.netwrote: Do you do completely asynch clunks or just the wait for the response?. it uses `completely' async clunks, which is why it can be broken. having the original process send the Tclunk and not wait for the Rclunk is

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
gee i thought i was the first to say deadly-embrace on this thread. it's not only problematic it's wrong. just reiterating what little shaun said circa 1999. brucee On Sat, Oct 30, 2010 at 3:02 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 17:01, Charles Forsyth

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
i don't believe that is possible in my implementation. will check. it was your implementation i was testing.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
on the other hand inferno's sys-export(2) services all requests (except Tflush) asynchronously, so the race will always be present. no, that mistakes the problem. without the change, the issuing process will see the clunk completed before it attempts any further operations: no race. with the

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Venkatesh Srinivas
erik quanstrom wrote: what's a reasonable definition of standard? I've been using 'decent' in much the same way 'standard' or 'disk' is being used; I'd actually prefer nemo's idea of a QTDECENT qidtype to marking the file server. The original QTDECENT proposal (actually originally inverted

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread David Leimbach
On Fri, Oct 29, 2010 at 8:49 AM, Charles Forsyth fors...@terzarima.netwrote: things up with standard (as opposed to synthetic) file systems? why should a synthetic file system (actually they are all synthetic, i think) be considered not standard? i thought file systems were the common

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 29 October 2010 17:17, Bruce Ellis bruce.el...@gmail.com wrote: gee i thought i was the first to say deadly-embrace on this thread. it's not only problematic it's wrong. just reiterating what little shaun said circa 1999. if deadlock is the issue, isn't it solved just as well by

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
I think functional programming or at least category theory gets you into these upper level abstract ways of thinking uh oh. is there an analogy to Godwin's Law for mentioning category theory?

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Charles Forsyth
Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how many file servers we can think of that are 'decent': fossil, kfs, ken, memfs,

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread erik quanstrom
I've been using 'decent' in much the same way 'standard' or 'disk' is being used; I'd actually prefer nemo's idea of a QTDECENT qidtype to marking the file server. The original QTDECENT proposal (actually originally inverted logic, in the form of QTCTL) said this about indecent files: this

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread erik quanstrom
On Fri Oct 29 13:15:45 EDT 2010, fors...@terzarima.net wrote: Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how many file

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread erik quanstrom
Category Theory really doesn't say too much in general, but oddly enough it applies nicely to computer science. What's that mean? :-) that they're both abstract nonsense. - erik

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread David Leimbach
On Fri, Oct 29, 2010 at 10:13 AM, Charles Forsyth fors...@terzarima.netwrote: I think functional programming or at least category theory gets you into these upper level abstract ways of thinking uh oh. is there an analogy to Godwin's Law for mentioning category theory? I hope not... I'm

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread David Leimbach
On Fri, Oct 29, 2010 at 10:17 AM, erik quanstrom quans...@labs.coraid.comwrote: On Fri Oct 29 13:15:45 EDT 2010, fors...@terzarima.net wrote: Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
who said deadlock. it's an easily reproducible situation. rattle the cage is not a solution. brucee On Sat, Oct 30, 2010 at 4:26 AM, erik quanstrom quans...@quanstro.net wrote: Category Theory really doesn't say too much in general, but oddly enough it applies nicely to computer science.  

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Eric Van Hensbergen
On Fri, Oct 29, 2010 at 12:18 PM, Charles Forsyth fors...@terzarima.net wrote: Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread David Leimbach
On Fri, Oct 29, 2010 at 10:26 AM, erik quanstrom quans...@quanstro.netwrote: Category Theory really doesn't say too much in general, but oddly enough it applies nicely to computer science. What's that mean? :-) that they're both abstract nonsense. - erik Yeah... the most fun I had

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Gorka Guardiola
Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how many file servers we can think of that are 'decent': fossil, kfs, ken, Decent

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread David Leimbach
On Fri, Oct 29, 2010 at 11:54 AM, Gorka Guardiola pau...@gmail.com wrote: Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 29 October 2010 18:47, Bruce Ellis bruce.el...@gmail.com wrote: who said deadlock. it's an easily reproducible situation. rattle the cage is not a solution. sorry then, i misunderstood you. what else did you mean by deadly embrace?

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread erik quanstrom
Let's try to define 'decent' for this thread -- a decent fileserver is one on which close()s do not have any client-visible or semantic effect other than to invalidate the Fid that was passed to them. Lets see how many file servers we can think of that are 'decent': fossil, kfs, ken,

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
back to school for roger On Sat, Oct 30, 2010 at 6:33 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 18:47, Bruce Ellis bruce.el...@gmail.com wrote: who said deadlock. it's an easily reproducible situation. rattle the cage is not a solution. sorry then, i misunderstood you.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Gorka Guardiola
On Oct 29, 2010, at 10:27 PM, Bruce Ellis bruce.el...@gmail.com wrote: back to school for roger On Sat, Oct 30, 2010 at 6:33 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 18:47, Bruce Ellis bruce.el...@gmail.com wrote: who said deadlock. it's an easily reproducible

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
that definition is wrong! On Sat, Oct 30, 2010 at 7:41 AM, Gorka Guardiola pau...@gmail.com wrote: On Oct 29, 2010, at 10:27 PM, Bruce Ellis bruce.el...@gmail.com wrote: back to school for roger On Sat, Oct 30, 2010 at 6:33 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010

[9fans] replica/pull as of today

2010-10-29 Thread ron minnich
trying to build an omap, I get a missing mousexy and mouseresize in libdraw. They are indeed not there at least in what I pulled. Any hints here? ron

Re: [9fans] replica/pull as of today

2010-10-29 Thread David du Colombier
trying to build an omap, I get a missing mousexy and mouseresize in libdraw. They are indeed not there at least in what I pulled. Any hints here? I had exactly the same problem. -- David du Colombier

Re: [9fans] replica/pull as of today

2010-10-29 Thread geoff
They are defined in port/devmouse.c. Did you get an updated beagle config file when you pulled? You should have.

Re: [9fans] replica/pull as of today

2010-10-29 Thread ron minnich
On Fri, Oct 29, 2010 at 2:52 PM, ge...@plan9.bell-labs.com wrote: They are defined in port/devmouse.c. there is no port/devmouse.c in my tree. Pull just done a few minutes ago. ron

Re: [9fans] replica/pull as of today

2010-10-29 Thread ron minnich
On Fri, Oct 29, 2010 at 2:58 PM, ron minnich rminn...@gmail.com wrote: On Fri, Oct 29, 2010 at 2:52 PM,  ge...@plan9.bell-labs.com wrote: They are defined in port/devmouse.c. there is no port/devmouse.c in my tree. Pull just done a few minutes ago. arg. no wait there is. Hold on. ron

Re: [9fans] replica/pull as of today

2010-10-29 Thread ron minnich
OK had to uncomment the mouse in the devs, and all was well. ron

Re: [9fans] replica/pull as of today

2010-10-29 Thread David du Colombier
They are defined in port/devmouse.c. Did you get an updated beagle config file when you pulled? You should have. No. It seems the problem is there. -- David du Colombier

Re: [9fans] replica/pull as of today

2010-10-29 Thread David du Colombier
OK had to uncomment the mouse in the devs, and all was well. It seems the replica database is not fully up to date, since the file /sys/src/9/omap/beagle contains the uncommented mouse on sources. -- David du Colombier

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bakul Shah
See EWD108 Een algorithme ter voorkoming van de dodelijke omarming. (An algorithm to avoid the deadly embrace.) in which Dijkstra describes his Bankers algorithm. 1965 or earlier. Of course, you may be looking at deadly embrace from a different point of view. On Sat, 30 Oct 2010 07:44:58 +1100

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
On 29 October 2010 21:44, Bruce Ellis bruce.el...@gmail.com wrote: that definition is wrong! so point us to the right one then.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
grab a book by hoare or morgan. brucee On Sat, Oct 30, 2010 at 9:39 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 21:44, Bruce Ellis bruce.el...@gmail.com wrote: that definition is wrong! so point us to the right one then.

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread roger peppe
the only book by hoare i've got (CSP) doesn't mention a deadly embrace. On 29 October 2010 23:43, Bruce Ellis bruce.el...@gmail.com wrote: grab a book by hoare or morgan. brucee On Sat, Oct 30, 2010 at 9:39 AM, roger peppe rogpe...@gmail.com wrote: On 29 October 2010 21:44, Bruce Ellis

Re: [9fans] A little more ado about async Tclunk

2010-10-29 Thread Bruce Ellis
well you need more books. On Sat, Oct 30, 2010 at 10:07 AM, roger peppe rogpe...@gmail.com wrote: the only book by hoare i've got (CSP) doesn't mention a deadly embrace. On 29 October 2010 23:43, Bruce Ellis bruce.el...@gmail.com wrote: grab a book by hoare or morgan. brucee On Sat, Oct