Reduce usage of fmt in LoggingHandler

[gorilla]

Reduce usage of fmt in LoggingHandler

[hjr265]

@kisielk I think it's possible to avoid the use of fmt altogether. By using io.WriteString and strconv.Itoa. Since the format verbs are either %s or %d. The buildCommonLogLine could then take a writer and write to it directly, instead of returning a string.

Although, if using fmt once per request is really okay, then yeah.. It is possible by moving a few things around may be.

[hjr265]

I can make this change and send you a pull request if that's okay..

[kisielk]

Go for it

On Tuesday, May 27, 2014, Mahmud Ridwan [email protected] wrote:

I can make this change and send you a pull request if that's okay..

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/4#issuecomment-44257743
.

-K

[kisielk]

However, please try benchmarking it to make sure the modified version is actually faster and does fewer allocations than the fmt version.

[hjr265]

I wrote a simple benchmark func

func BenchmarkWriteLog(b *testing.B) {
    loc, err := time.LoadLocation("Europe/Warsaw")
    if err != nil {
        b.Fatalf(err.Error())
    }
    ts := time.Date(1983, 05, 26, 3, 30, 45, 0, loc)

    req := newRequest("GET", "http://example.com")
    req.RemoteAddr = "192.168.100.5"

    b.ResetTimer()

    buf := &bytes.Buffer{}
    for i := 0; i < b.N; i++ {
        buf.Reset()
        writeLog(buf, req, ts, http.StatusUnauthorized, 500)
    }
}

For current implementation, I get this:

BenchmarkWriteLog     500000          3351 ns/op

For the modified implementation (with no fmt at all), I get this:

BenchmarkWriteLog    1000000          1394 ns/op

[kisielk]

That certainly looks promising. How about memory usage? There's a benchmark
flag to measure allocations as well. I expect it will be lower too.

On Wednesday, May 28, 2014, Mahmud Ridwan [email protected] wrote:

I wrote a simple benchmark function

func BenchmarkWriteLog(b *testing.B) {
loc, err := time.LoadLocation("Europe/Warsaw")
if err != nil {
b.Fatalf(err.Error())
}
ts := time.Date(1983, 05, 26, 3, 30, 45, 0, loc)

req := newRequest("GET", "http://example.com")
req.RemoteAddr = "192.168.100.5"

buf := &bytes.Buffer{}
for i := 0; i < b.N; i++ {
    buf.Reset()
    writeLog(buf, req, ts, http.StatusUnauthorized, 500)
}}

For current implementation, I get this:

BenchmarkWriteLog 500000 3351 ns/op

For the modified implementation (with no fmt at all), I get this:

BenchmarkWriteLog 1000000 1394 ns/op

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/4#issuecomment-44383295
.

-K

[hjr265]

Ran $ go test -bench . -benchmem

For current implementation:

BenchmarkWriteLog     500000          3287 ns/op         338 B/op         11 allocs/op

For the modified implementation (#13; with no fmt at all):

BenchmarkWriteLog    1000000          1412 ns/op         162 B/op          5 allocs/op