``` CSV parsing, BEFORE: BenchmarkReaderBasic-12 2842 407533 ns/op 397860 B/op 957 allocs/op BenchmarkReaderReplace-12 2718 429914 ns/op 397844 B/op 957 allocs/op BenchmarkReaderReplaceTwo-12 2718 435556 ns/op 397855 B/op 957 allocs/op BenchmarkAggregateCount_100K-12 171 6798974 ns/op 16667102 B/op 308077 allocs/op BenchmarkAggregateCount_1M-12 19 65657411 ns/op 168057743 B/op 3146610 allocs/op BenchmarkSelectAll_10M-12 1 20882119900 ns/op 2758799896 B/op 41978762 allocs/op CSV parsing, AFTER: BenchmarkReaderBasic-12 3721 312549 ns/op 101920 B/op 338 allocs/op BenchmarkReaderReplace-12 3776 318810 ns/op 101993 B/op 340 allocs/op BenchmarkReaderReplaceTwo-12 3610 330967 ns/op 102012 B/op 341 allocs/op BenchmarkAggregateCount_100K-12 295 4149588 ns/op 3553623 B/op 103261 allocs/op BenchmarkAggregateCount_1M-12 30 37746503 ns/op 33827931 B/op 1049435 allocs/op BenchmarkSelectAll_10M-12 1 17608495800 ns/op 1416504040 B/op 21007082 allocs/op ~ benchcmp old.txt new.txt benchmark old ns/op new ns/op delta BenchmarkReaderBasic-12 407533 312549 -23.31% BenchmarkReaderReplace-12 429914 318810 -25.84% BenchmarkReaderReplaceTwo-12 435556 330967 -24.01% BenchmarkAggregateCount_100K-12 6798974 4149588 -38.97% BenchmarkAggregateCount_1M-12 65657411 37746503 -42.51% BenchmarkSelectAll_10M-12 20882119900 17608495800 -15.68% benchmark old allocs new allocs delta BenchmarkReaderBasic-12 957 338 -64.68% BenchmarkReaderReplace-12 957 340 -64.47% BenchmarkReaderReplaceTwo-12 957 341 -64.37% BenchmarkAggregateCount_100K-12 308077 103261 -66.48% BenchmarkAggregateCount_1M-12 3146610 1049435 -66.65% BenchmarkSelectAll_10M-12 41978762 21007082 -49.96% benchmark old bytes new bytes delta BenchmarkReaderBasic-12 397860 101920 -74.38% BenchmarkReaderReplace-12 397844 101993 -74.36% BenchmarkReaderReplaceTwo-12 397855 102012 -74.36% BenchmarkAggregateCount_100K-12 16667102 3553623 -78.68% BenchmarkAggregateCount_1M-12 168057743 33827931 -79.87% BenchmarkSelectAll_10M-12 2758799896 1416504040 -48.66% ``` ``` BenchmarkReaderHuge/97K-12 2200 540840 ns/op 184.32 MB/s 1604450 B/op 687 allocs/op BenchmarkReaderHuge/194K-12 1522 752257 ns/op 265.04 MB/s 2143135 B/op 1335 allocs/op BenchmarkReaderHuge/389K-12 1190 947858 ns/op 420.69 MB/s 3221831 B/op 2630 allocs/op BenchmarkReaderHuge/778K-12 806 1472486 ns/op 541.61 MB/s 5201856 B/op 5187 allocs/op BenchmarkReaderHuge/1557K-12 426 2575269 ns/op 619.36 MB/s 9101330 B/op 10233 allocs/op BenchmarkReaderHuge/3115K-12 286 4034656 ns/op 790.66 MB/s 12397968 B/op 16099 allocs/op BenchmarkReaderHuge/6230K-12 172 6830563 ns/op 934.05 MB/s 16008416 B/op 26844 allocs/op BenchmarkReaderHuge/12461K-12 100 11409467 ns/op 1118.39 MB/s 22655163 B/op 48107 allocs/op BenchmarkReaderHuge/24922K-12 66 19780395 ns/op 1290.19 MB/s 35158559 B/op 90216 allocs/op BenchmarkReaderHuge/49844K-12 34 37282559 ns/op 1369.03 MB/s 60528624 B/op 174497 allocs/op ```
94 lines
1.9 KiB
Go
94 lines
1.9 KiB
Go
/*
|
|
* MinIO Cloud Storage, (C) 2019 MinIO, Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package csv
|
|
|
|
import (
|
|
"bytes"
|
|
"io"
|
|
)
|
|
|
|
// recordTransform will convert records to always have newline records.
|
|
type recordTransform struct {
|
|
reader io.Reader
|
|
// recordDelimiter can be up to 2 characters.
|
|
recordDelimiter []byte
|
|
oneByte []byte
|
|
useOneByte bool
|
|
}
|
|
|
|
func (rr *recordTransform) Read(p []byte) (n int, err error) {
|
|
if rr.useOneByte {
|
|
p[0] = rr.oneByte[0]
|
|
rr.useOneByte = false
|
|
n, err = rr.reader.Read(p[1:])
|
|
n++
|
|
} else {
|
|
n, err = rr.reader.Read(p)
|
|
}
|
|
|
|
if err != nil {
|
|
return n, err
|
|
}
|
|
|
|
// Do nothing if record-delimiter is already newline.
|
|
if string(rr.recordDelimiter) == "\n" {
|
|
return n, nil
|
|
}
|
|
|
|
// Change record delimiters to newline.
|
|
if len(rr.recordDelimiter) == 1 {
|
|
for idx := 0; idx < len(p); {
|
|
i := bytes.Index(p[idx:], rr.recordDelimiter)
|
|
if i < 0 {
|
|
break
|
|
}
|
|
idx += i
|
|
p[idx] = '\n'
|
|
}
|
|
return n, nil
|
|
}
|
|
|
|
// 2 characters...
|
|
for idx := 0; idx < len(p); {
|
|
i := bytes.Index(p[idx:], rr.recordDelimiter)
|
|
if i < 0 {
|
|
break
|
|
}
|
|
idx += i
|
|
|
|
p[idx] = '\n'
|
|
p = append(p[:idx+1], p[idx+2:]...)
|
|
n--
|
|
}
|
|
|
|
if p[n-1] != rr.recordDelimiter[0] {
|
|
return n, nil
|
|
}
|
|
|
|
if _, err = rr.reader.Read(rr.oneByte); err != nil {
|
|
return n, err
|
|
}
|
|
|
|
if rr.oneByte[0] == rr.recordDelimiter[1] {
|
|
p[n-1] = '\n'
|
|
return n, nil
|
|
}
|
|
|
|
rr.useOneByte = true
|
|
return n, nil
|
|
}
|