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Groups > comp.lang.forth > #41709
| From | Bernd Paysan <bernd.paysan@gmx.de> |
|---|---|
| Newsgroups | comp.lang.forth |
| Subject | Re: GA144 use cases |
| Date | 2015-09-03 23:58 +0200 |
| Organization | A noiseless patient Spider |
| Message-ID | <msafnk$9sk$1@dont-email.me> (permalink) |
| References | <ms0v7i$icg$1@news.mixmin.net> <94781700948432@frunobulax.edu> |
Marcel Hendrix wrote: > Bernd Paysan <bernd.paysan@gmx.de> writes Re: GA144 use cases > >> Anton Ertl wrote: >>> And the same goes for paragraphs. OTOH, TeX is so fast on modern CPUs >>> that one can really say that paralellizing it would not enhance it. >>> Also, parallelizing it would require quite a bit of effort. > > The NGSPICE manual is 650 pages and takes more than two minutes to > process. When maintaining the manual (small, infrequent edits) that is too > long and quality suffers (one doesn't do a single edit, or one doesn't > want to check the outcome). That gives an estimate about how long it takes per paragraph: Let's assume 10 paragraphs per page (some of them small, some larger), you maybe have 6000 paragraphs in your document. Makes 20ms per paragraph. That's in the ballpark where the microsecond IPC is a non-issue, and where algorithmic improvements are probably an even lower-hanging fruit. > That approach would suffer unbearably from Amdahl's law, doesn't it? When it's really 20ms per paragraph, and maybe 2ms per variant, no. >> The problem with parallelism I have is not that I can't imagine it, but >> that >> the overhead is too large. E.g. take net2o: I send and receive messages >> (each takes time in the kernel), and I decrypt and encrypt them. With a >> four-core CPU, I could run that in four tasks. > > Why not have a writable instruction set for these kind of problems? If Intel puts some FPGA stuff into each core (after all, they bought Altera), and connects the FPGAs together, that would solve part of the job. The other part, keeping some contexts in the core's large register file, but not executing the instructons and wait for wakeup, needs to go deeper in the details. However, for the crypto stuff, I'd probably rather use the FPGA to implement the crypto primitive (Keccak) directly, that's using a few thousand LEs with a potentially higher speedup than parallelization. >> However, when trying that, I found that the IPC is killing the >> performance. These tasks don't take too much time - en/decrypting a 1k >> block takes 10k cycles, and the IPC then takes about as long, too, so all >> the gain goes down the flush. > > I am an ngspice maintainer and see the same thing there. The actual device > code that is executed per time step is almost always so small that e.g. > openmp does not work. Although all cores run at 100%, the simulation takes > 20% longer. It works a little bit for some transistor models that are > extremely lengthy, but there Amdahl's law cuts in again when all other > processing is included. Yes, that's why we must reduce the communication overhead. Amdahl's law is there, because communication between threads is way too expensive. -- Bernd Paysan "If you want it done right, you have to do it yourself" net2o ID: kQusJzA;7*?t=uy@X}1GWr!+0qqp_Cn176t4(dQ* http://bernd-paysan.de/
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GA144 use cases dunno <dunno@dunno.dunno> - 2015-08-31 07:20 +0000
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-08-31 09:55 -0400
Re: GA144 use cases Syd Rumpo <usenet@nononono.co.uk> - 2015-08-31 16:49 +0100
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-08-31 18:35 -0400
Re: GA144 use cases Dennis Ruffer <daruffer@gmail.com> - 2015-08-31 19:08 -0700
Re: GA144 use cases Mux <Yvo.Zoer@gmail.com> - 2015-09-02 10:57 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 14:17 -0400
Re: GA144 use cases Mux <Yvo.Zoer@gmail.com> - 2015-09-02 11:28 -0700
Re: GA144 use cases hughaguilar96@gmail.com - 2015-09-02 13:41 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 16:50 -0400
Re: GA144 use cases Mux <Yvo.Zoer@gmail.com> - 2015-09-02 15:03 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 18:18 -0400
Re: GA144 use cases Mux <Yvo.Zoer@gmail.com> - 2015-09-02 16:14 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 20:40 -0400
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-02 17:53 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 21:25 -0400
Re: GA144 use cases Mux <Yvo.Zoer@gmail.com> - 2015-09-02 22:28 -0700
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-02 22:53 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-03 11:32 -0400
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-03 11:57 -0700
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-03 10:35 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-03 15:54 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-03 16:11 +0000
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-03 13:06 -0400
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-04 08:07 +0000
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-04 11:49 -0400
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-05 11:06 +0000
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-05 09:05 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-05 12:59 -0400
Re: GA144 use cases mhx@iae.nl - 2015-09-05 10:56 -0700
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-06 14:29 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-03 22:08 +0200
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-03 14:00 -0700
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-04 01:28 +0200
Re: GA144 use cases franck.bensusan@gmail.com - 2015-09-03 23:04 -0700
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-04 08:24 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-04 15:09 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-05 15:10 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-05 22:04 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-06 14:51 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-06 22:51 +0200
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-06 17:30 -0700
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-04 22:27 -0700
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-05 13:07 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-05 11:22 +0000
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-04 08:14 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-04 15:13 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-05 16:06 +0000
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-05 21:05 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-06 14:37 +0000
Re: GA144 use cases Andrew Haley <andrew29@littlepinkcloud.invalid> - 2015-11-30 04:17 -0600
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-12-01 23:06 +0100
Re: GA144 use cases Mark Wills <markwills1970@gmail.com> - 2015-09-03 00:05 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-03 13:08 -0400
Re: GA144 use cases forther <forther@gmail.com> - 2015-09-07 11:26 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-02 15:15 -0400
Re: GA144 use cases forther <forther@gmail.com> - 2015-09-07 11:21 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-11-30 16:33 -0500
Re: GA144 use cases forther <forther@gmail.com> - 2015-12-03 12:12 -0800
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-12-03 16:10 -0500
Re: GA144 use cases Jason Damisch <jasondamisch@yahoo.com> - 2015-09-02 12:10 -0700
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-03 01:27 -0700
Re: GA144 use cases Syd Rumpo <usenet@nononono.co.uk> - 2015-09-03 13:32 +0100
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-03 11:32 -0400
Re: GA144 use cases mhx@iae.nl (Marcel Hendrix) - 2015-09-03 18:57 +0200
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-03 23:58 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-04 07:52 +0000
Re: GA144 use cases Waldek Hebisch <hebisch@antispam.uni.wroc.pl> - 2015-09-05 16:32 +0000
Re: GA144 use cases mhx@iae.nl - 2015-09-05 10:52 -0700
Re: GA144 use cases Bernd Paysan <bernd.paysan@gmx.de> - 2015-09-05 22:11 +0200
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-06 14:18 +0000
Re: GA144 use cases anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-09-07 07:49 +0000
Re: GA144 use cases Waldek Hebisch <hebisch@math.uni.wroc.pl> - 2015-09-05 23:42 +0000
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-05 17:25 -0700
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-07 03:18 -0700
Re: GA144 use cases Raimond Dragomir <raimond.dragomir@gmail.com> - 2015-09-07 03:31 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-07 15:06 -0400
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-08 21:41 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-09 02:54 -0400
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-09 03:02 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-09 16:55 -0400
Re: GA144 use cases Paul Rubin <no.email@nospam.invalid> - 2015-09-09 20:12 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-09 23:40 -0400
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-09 23:43 -0400
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-10 00:07 -0400
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-09 21:55 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-10 01:43 -0400
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-09 23:49 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-10 14:43 -0400
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-10 16:10 -0400
Re: GA144 use cases Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2015-09-12 03:15 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-12 10:28 -0400
Re: GA144 use cases Greg <abiforth@gmail.com> - 2015-09-13 13:05 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-13 18:59 -0400
Re: GA144 use cases Greg <abiforth@gmail.com> - 2015-09-13 18:42 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-13 22:47 -0400
Re: GA144 use cases Greg <abiforth@gmail.com> - 2015-09-13 21:24 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-14 02:00 -0400
Re: GA144 use cases borota@gmail.com - 2015-09-14 08:35 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-14 12:06 -0400
Re: GA144 use cases borota@gmail.com - 2015-09-14 09:33 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-14 13:25 -0400
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-14 14:17 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-14 18:12 -0400
Re: GA144 use cases Greg <schmegner@gmail.com> - 2015-09-14 18:15 -0700
Re: GA144 use cases rickman <gnuarm@gmail.com> - 2015-09-14 22:16 -0400
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-18 14:50 -0700
Re: GA144 use cases Jason Damisch <jasondamisch@yahoo.com> - 2015-09-18 15:11 -0700
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-19 05:32 -0700
Re: GA144 use cases Dennis Ruffer <daruffer@gmail.com> - 2015-09-19 08:39 -0700
Re: GA144 use cases Greg <borota@gmail.com> - 2015-09-20 19:03 -0700
Re: GA144 use cases Dennis Ruffer <daruffer@gmail.com> - 2015-09-21 06:44 -0700
Re: GA144 use cases Dennis Ruffer <daruffer@gmail.com> - 2015-09-22 13:10 -0700
Re: GA144 use cases Mark Wills <markwills1970@gmail.com> - 2015-09-18 16:18 -0700
Re: GA144 use cases schmegner@gmail.com - 2015-09-14 18:21 -0700
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