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authorYale AI Dept <ai@nebula.cs.yale.edu>1993-07-14 13:08:00 -0500
committerDuncan McGreggor <duncan.mcgreggor@rackspace.com>1993-07-14 13:08:00 -0500
commit4e987026148fe65c323afbc93cd560c07bf06b3f (patch)
tree26ae54177389edcbe453d25a00c38c2774e8b7d4 /doc
Import to github.
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diff --git a/doc/announcement b/doc/announcement
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+
+ Announcing the release of Yale Haskell 2.0.5
+
+We are releasing the latest version of the Yale Haskell system,
+Y2.0.5, in source form. This fixes a number of minor problems in the
+2.0.5a release (for Sparc only) and should be relatively bug free.
+
+Yale Haskell can be built from sources using CMU Common Lisp, Lucid
+Common Lisp, Allegro Common Lisp, or Harlequin LispWorks. The system
+may also build on akcl but the performance is very poor.
+
+Compiled versions of the system are available for Sparc systems running
+SunOS 4.1.2 and Sparc 10's (sun4m) running 4.1.3. Anyone building a system
+using CMU lisp on a different platform should let us know and we will
+add more executables to the ftp area. Look at the README for further
+information.
+
+This release features an X window interface. Using CLX, the full
+functionality of X windows has been made available at the Haskell
+level. There is also a Haskell <-> Lisp interface similar to the C
+interface in the Glasgow system.
+
+
+Our system is available for anonymous ftp from the Yale Haskell ftp site:
+
+ Site Host name Raw IP address
+ Yale nebula.cs.yale.edu 128.36.13.1
+
+All files are in the directory pub/haskell/yale.
+
+haskell-source-205.tar.gz -- The full sources
+haskell-205-<machine+OS>.tar.gz
+Compiling from scratch will take an hour or two, depending on system
+resources. The file $HASKELL/com/<your-lisp>/README will contain
+complete building instructions.
+
+To obtain Yale Haskell via ftp:
+
+ - Move to the directory where you intend to place Yale Haskell
+ - Ftp to nebula and login anonymously
+ - cd to pub/haskell/yale
+ - Get the tar file: get haskell-source-205.tar.gz (a .Z file is available
+ for those without gzip).
+ - Unzip the file: (your zip utility may have a different name)
+ gzip -d *.gz
+ - Untar the file: tar xf *.tar
+ - Consult the documentation for further instructions. Either print
+ out the reference manual in doc/manual/haskell.dvi or look at
+ install.verb in the same directory.
+
+Send any comments or questions to haskell-request@cs.yale.edu
+
+
+New features in this release include:
+
+ * Much better optimization
+ * Monadic I/O
+ * A general Haskell to Lisp interface
+ * An X window interface
+ * Strictness annotations and strict data constructors
+ * Lots of bugs fixed
+ * Improvements to the tutorial and Emacs interface
+ * Ported to all major Lisp systems
+
diff --git a/doc/comparison b/doc/comparison
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+
+ Different Versions of Yale Haskell Compared
+ -------------------------------------------
+
+
+There are currently three different platforms running Yale Haskell.
+Yale Haskell runs on Lucid Common Lisp, CMU Common Lisp, and AKCL. This
+document describes the differences between these systems.
+
+Differences in performance between the different versions of Yale
+Haskell reflect the underlying Lisp systems. The better the Lisp
+system, the better the Haskell system built on it. However, getting
+optimal performance from our Haskell system on top of a Common Lisp
+system requires careful attention to the underlying compiler. Small
+changes in the optimization settings or the addition of crucial
+declarations can make significant differences in performance. We have
+been doing most of our work using the Lucid system and have tuned it
+more than the others. These comparisons are greatly influenced by the
+amount of time we have spent tuning the system: the CMU version has
+been tuned only a little and the AKCL version hardly at all.
+
+
+ Methodology
+
+The following timings are only approximate. They were obtained using
+the timing functions provided by the Common Lisp system. All timings
+were done on an unloaded Sparc 1. No attempt was made to account for
+garbage collection, differences in heap size, or similar factors. We
+don't intend these benchmark results to be taken as an exhaustive
+comparison of the different Lisp implementations involved.
+
+
+ Portability
+
+We have had no trouble moving our system to different hardware
+platforms under the same Lisp system. Since the release is in source
+form, we expect that users will be able to build on any hardware
+platform supported by one the Lisps we have ported to. Probably the
+only real constraint on portability is the requirement for a large
+virtual memory space.
+
+From the comp.lang.lisp FAQ:
+
+ Lucid Common Lisp runs on a variety of platforms, including PCs (AIX),
+ Apollo, HP, Sun-3, Sparc, IBM RT, IBM RS/6000, Decstation 3100,
+ Silicon Graphics, and Vax.
+
+ CMU Common Lisp is free, and runs on Sparcs (Mach and SunOs),
+ DecStation 3100 (Mach), IBM RT (Mach) and requires 16mb RAM, 25mb disk.
+
+ Kyoto Common Lisp (KCL) is free, but requires a license. Conforms to CLtL1.
+ It is available by anonymous ftp from rascal.ics.utexas.edu [128.83.138.20],
+ cli.com [192.31.85.1], or [133.11.11.11] (a machine in Japan)
+ in the directory /pub. AKCL is in the file akcl-xxx.tar.Z (take the
+ highest value of xxx). To obtain KCL, one must first sign and mail a
+ copy of the license agreement to: Special Interest Group in LISP,
+ c/o Taiichi Yuasa, Department of Computer Science, Toyohashi
+ University of Technology, Toyohashi 441, JAPAN. Runs on Sparc,
+ IBM RT, RS/6000, DecStation 3100, hp300, hp800, Macintosh II (under AUX),
+ mp386, IBM PS2, Silicon Graphics 4d, Sun3, Sun4, Sequent Symmetry,
+ IBM 370, NeXT and Vax. A port to DOS is in beta test as
+ math.utexas.edu:pub/beta2.zip.
+
+We have not yet completed ports of Yale Haskell to any other Lisp
+implementations, although we are likely to do so in the future.
+
+
+ System Size
+
+The overall size of the Haskell system depends on the size of the
+underlying Lisp system and how much unnecessary Lisp overhead has been
+removed for the system. We have removed large Lisp packages (like
+CLOS or CLX), but have not attempted to do any tree shaking. The size
+of the saved images (including the Lisp system, the Haskell compiler,
+and the compiled prelude) is
+
+Image Size:
+
+Lucid 10 meg
+CMU 18 meg
+AKCL 11 meg
+
+The larger size of the CMU system is probably an artifact of their way
+of saving the system.
+
+
+ Compilation Time
+
+There are three possible ways to compile a Haskell program. All
+Haskell programs must be translated into Lisp. The generated Lisp can
+then be interpreted, using no additional compilation time; compiled
+with a `fast' but nonoptimizing Lisp compiler; or compiled with the
+`slow' compiler that aggressively attempts to perform as many
+optimizations as possible.
+
+To time the `fast', nonoptimizing compiler, we have been using
+
+(PROCLAIM '(OPTIMIZE (SPEED 3) (SAFETY 0) (COMPILATION-SPEED 3)))
+
+and for the `slow', fully optimizing compiler, we have been using
+
+(PROCLAIM '(OPTIMIZE (SPEED 3) (SAFETY 0) (COMPILATION-SPEED 0)))
+
+so that the only difference is in the COMPILATION-SPEED quality.
+Lucid does, in fact, provide two completely different compilers that
+correspond to these optimize settings. For all three implementations,
+it appears that that the effect of a higher compilation speed setting
+is primarily in being less aggressive about inlining and making use of
+type declarations.
+
+The Haskell system itself (including the Prelude) is normally built
+with the fully optimizing compiler.
+
+To show just the Haskell to Lisp compilation time, here are the times
+needed to compile the Prelude (about 2500 lines of Haskell code).
+This does not include the time in the Lisp compiler or starting up the
+system.
+
+Time to compile the Prelude into Lisp: (CPU times)
+
+Lucid 111 sec
+CMU 87 sec
+AKCL 576 sec
+
+Running the Lisp compiler on the generated code takes far longer than
+running the Haskell compiler to produce the Lisp code. For example,
+the optimizing Lucid compiler takes 47 minutes to compile the Prelude
+(about x20 slower than Haskell -> Lisp). The nonoptimizing compiler
+is significantly faster but generates poorer code.
+
+The following times are the Lisp compilation time for the Prolog
+interpreter (found in the demo directory of our release):
+
+Lucid - interpreted 8.8 sec Haskell -> Lisp
+Lucid - nonopt 20.0 sec Lisp -> Machine code
+Lucid - optimizing 320.0 sec Lisp -> Machine code
+CMU - interpreted 12.4 sec Haskell -> Lisp
+CMU - nonopt 121.0 sec Lisp -> Machine code
+CMU - optimizing 152.8 sec Lisp -> Machine code
+AKCL - interpreted 47.8 sec Haskell -> Lisp
+AKCL - nonopt ~180 sec Lisp -> Machine code
+AKCL - optimizing ~360 sec Lisp -> Machine code
+
+The AKCL timings are only approximate, because the Lisp timing
+functions do not capture the time spent in the C compiler.
+
+
+Code Speed
+
+The speed of the Haskell program depends on whether the Lisp code
+has been compiled with the optimizing or nonoptimizing compiler, or
+is running interpretively.
+
+The first benchmark is nfib, which indicates the basic speed of
+function calling and Int arithmetic.
+
+module Main where
+
+nfib :: Int -> Int
+nfib 0 = 1
+nfib 1 = 1
+nfib n = nfib (n-1) + nfib (n-2)
+
+
+ nfib 20 nfib 30
+Lucid (Interpreted) 116 sec *
+Lucid (nonopt) 0.14 sec 9.4 sec
+Lucid (optimizing) 0.08 sec 4.8 sec
+CMU (Interpreted) 23.8 sec *
+CMU (nonopt) 0.24 sec 6.9 sec
+CMU (optimizing) 0.11 sec 7.0 sec
+AKCL (Interpreted) 141 sec *
+AKCL (nonopt) 0.20 sec 21.3 sec
+AKCL (optimizing) 0.15 sec 18.2 sec
+
+* Too slow to benchmark
+
+For other data types, there was no significant difference betwen
+optimizing and nonoptimizing compilation in any of the systems.
+Changing the signature of nfib to Integer -> Integer:
+
+ nfib 20 nfib 30
+Lucid (interpreted) 140 sec *
+Lucid (compiled) 0.18 sec 10.2 sec
+CMU (interpreted) 24.2 sec *
+CMU (compiled) 0.16 sec 10.5 sec
+AKCL (interpreted) 145 sec *
+AKCL (compiled) 1.07 sec 127 sec
+
+Nfib with signature Float -> Float:
+
+ nfib 20 nfib 30
+Lucid (interpreted) 222 sec *
+Lucid (compiled) 16.4 sec 2416 sec
+CMU (interpreted) 44.2 sec *
+CMU (compiled) 1.61 sec 352 sec
+AKCL (interpreted) 161 sec *
+AKCL (compiled) 103 sec *
+
+Overloaded functions run considerably slower than nonoverloaded
+functions. By allowing nfib to remain overloaded, Num a => a -> a,
+and using the Int overloading the same benchmarks run much slower.
+Again, there is no real difference between the different compiler
+optimization settings.
+
+ nfib 15 nfib 20
+Lucid (interpreted) 14.2 sec 156 sec
+Lucid (compiled) 0.97 sec 9.3 sec
+CMU (interpreted) 23.8 sec 155 sec
+CMU (compiled) 0.89 sec 15.6 sec
+AKCL (interpreted) 30.8 sec 387 sec
+AKCL (compiled) 10.3 sec 119 sec
+
+Basic Haskell data structuring operations (pattern matching and
+construction) can be tested using another version of nfib which uses
+natural numbers:
+
+ data Nat = Z | S Nat
+
+The difference betwen CMU and Lucid here is consistent with other
+benchmarks that manipulate structures.
+
+ nfib 10 nfib 15
+Lucid (Interpreted) 1.39 sec 26.7 sec
+Lucid (compiled) 0.26 sec 2.28 sec
+CMU (interpreted) 3.1 sec <stack overflow>
+CMU (compiled) 0.16 sec 0.54 sec
+AKCL (Interpreted) 4.25 sec <stack overflow>
+AKCL (compiled) 0.21 sec 13.9 sec
+
+
+ A Large Program
+
+For a final benchmark, we use the Prolog interpreter as a way of
+getting a feel for general performance of larger programs. This
+program is typical of symbolic (as opposed to numeric) computation.
+
+Time to solve append(X,Y,cons(a,cons(b,cons(c,nil)))):
+
+Lucid 12.2 sec
+CMU 12.0 sec
+AKCL 69.1 sec
+
+My interpretation of this result is that although Lucid is a bit
+slower on the previous small benchmarks, it makes up for this is
+larger programs where advantages like better instruction scheduling,
+register allocation, or memory usage may make a difference. In
+general, Lucid and CMU are very similar in performance for larger
+programs.
+
+
+ Conclusions
+
+Briefly stated, the pluses and minuses of each system are as follows:
+
+Lucid (4.0.0):
+ + Development (nonoptimizing) compiler is very fast
+ + Fast Haskell -> Lisp compilation
+ + Generates good code
+ + Very robust
+ - Costs money
+ - Slow floating point code
+ - Fairly slow interpreter
+ - The production (optimizing) compiler is extremely slow.
+
+CMU (16e):
+ + Free
+ + As fast as Lucid for Haskell -> Lisp
+ + Good floating point performance
+ + Generated code is very fast
+ + Fast interpreter
+ - Slow Lisp -> machine code compilation
+ - Doesn't run on many systems
+
+AKCL (1.615):
+ + Free
+ + Widely portable
+ - Slow (generally 3 - 5 times slower, sometimes much worse)
+ - Flakey (tends to core dump on errors, choke on large programs, etc.)
+
+Generally, using the fully optimizing compiler seems to be useful only
+in code involving Int arithmetic.
+
+The fast compiler for Lucid is a big advantage, delivering by far the
+fastest compilation to machine code with relatively little loss in
+speed compared to the optimizing compiler.
+
+
+ Yale Haskell Group
+ September 25, 1992
+
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