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improve myrandom() in fasta.

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add script to automate timing

R=rsc
DELTA=78  (68 added, 0 deleted, 10 changed)
OCL=32729
CL=32732
This commit is contained in:
Rob Pike 2009-08-04 14:07:17 -07:00
parent 9ae42ee87f
commit 0444da91c0
3 changed files with 81 additions and 10 deletions
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22
test/bench/fasta.go
View file

@ -66,7 +66,7 @@ type AminoAcid struct {
var lastrandom uint32 = 42
// Random number between 0.0 and 1.0
func myrandom() float {
func Zmyrandom() float {
const (
IM = 139968;
IA = 3877;
@ -74,7 +74,25 @@ func myrandom() float {
)
lastrandom = (lastrandom * IA + IC) % IM;
// Integer to float conversions are faster if the integer is signed.
return float(lastrandom) / IM;
return float(int32(lastrandom)) / IM;
}
// TODO: delete this when compiler does the reduction for us
func
myrandom() float
{
const (
IM = 139968;
IA = 3877;
IC = 29573;
S = 46;
IM1 = ((1<<S) + IM) / IM;
)
n := (lastrandom * IA + IC);
q := uint32((uint64(n) * IM1) >> S);
lastrandom = n - q*IM;
return float(int32(lastrandom)) / IM;
}
func AccumulateProbabilities(genelist []AminoAcid) {

31
test/bench/timing.log
View file

@ -6,13 +6,28 @@ First version of fasta. Translation of fasta.c, fetched from
http://shootout.alioth.debian.org/u32q/benchmark.php?test=fasta&lang=gpp&id=4
fasta -n 25000000
[gcc -O2 fasta.c 5.98u 0.00s 6.01r]
gccgo -O2 8.82u 0.02s 8.85r
6g 13.50u 0.02s 13.53r
6g -B 12.99u 0.02s 13.02r
gcc -O2 fasta.c 5.98u 0.00s 6.01r
gccgo -O2 fasta.go 8.82u 0.02s 8.85r
6g fasta.go 13.50u 0.02s 13.53r
6g -B fata.go 12.99u 0.02s 13.02r
Aug 4 2009
[added timing.sh]
# myrandom:
# hand-written optimization of integer division
# use int32->float conversion
fasta -n 25000000
gcc -O2 fasta.c 5.99u 0.00s 6.00r
gccgo -O2 fasta.go 8.82u 0.02s 8.85r
gc fasta 10.70u 0.00s 10.77r
gc_B fasta 10.09u 0.03s 10.12r
reverse-complement < output-of-fasta-25000000
[gcc -O2 reverse-complement.c 2.03u 0.84s 13.04r]
gccgo -O2 6.47u 1.14s 15.58r
6g 6.55u 1.21s 15.45r
6g -B 6.19u 1.26s 15.64r
gcc -O2 reverse-complement.c 2.04u 0.94s 10.54r
gccgo -O2 reverse-complement.go 6.54u 0.63s 7.17r
gc reverse-complement 6.55u 0.70s 7.26r
gc_B reverse-complement 6.32u 0.70s 7.10r
nbody -n 50000000
gcc -O2 nbody.c 21.33u 0.00s 21.34r

38
test/bench/timing.sh Executable file
View file

@ -0,0 +1,38 @@
#!/bin/sh
# Copyright 2009 The Go Authors. All rights reserved.
# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file.
set -e
. $GOROOT/src/Make.$GOARCH
gc() {
$GC $1.go; $LD $1.$O
}
gc_B() {
$GC -B $1.go; $LD $1.$O
}
run() {
echo -n ' '$1' '
$1
shift
(/home/r/plan9/bin/time $* 2>&1 >/dev/null) | sed 's/r.*/r/'
}
echo 'fasta -n 25000000'
run 'gcc -O2 fasta.c' a.out 25000000
#run 'gccgo -O2 fasta.go' a.out -n 25000000 #commented out until WriteString is in bufio
run 'gc fasta' $O.out -n 25000000
run 'gc_B fasta' $O.out -n 25000000
echo
6.out -n 25000000 > x
echo 'reverse-complement < output-of-fasta-25000000'
run 'gcc -O2 reverse-complement.c' a.out 25000000 < x
run 'gccgo -O2 reverse-complement.go' a.out -n 25000000 < x
run 'gc reverse-complement' $O.out -n 25000000 < x
run 'gc_B reverse-complement' $O.out -n 25000000 < x
rm x