perf: human log sink performance bump via reduction of allocs/total allocated memory #220
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Signed-off-by: Callum Styan <callumstyan@gmail.com>
Signed-off-by: Callum Styan <callumstyan@gmail.com>
…e the optimized version should return an error Signed-off-by: Callum Styan <callumstyan@gmail.com>
Pull Request Test Coverage Report for Build bb87268ba9bc796f570dc37547e5f0281129ddf5-PR-220Details
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cstyan
changed the title
Signed-off-by: Callum Styan <callumstyan@gmail.com>
Signed-off-by: Callum Styan <callumstyan@gmail.com>
…ne very specific case that should never happen if we're actually going to OOM via logging it would panic Signed-off-by: Callum Styan <callumstyan@gmail.com>
… files for new test cases Signed-off-by: Callum Styan <callumstyan@gmail.com>
Signed-off-by: Callum Styan <callumstyan@gmail.com>
Emyrk
reviewed
Nov 14, 2025
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| level := ent.Level.String() | ||
| level = strings.ToLower(level) | ||
| if len(level) > 4 { | ||
| level = level[:4] | ||
| } | ||
| level = "[" + level + "]" |
Member
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wow this old code was kinda dumb in comparison.
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| func bracketedLevel(l slog.Level) string { | ||
| switch l { | ||
| case slog.LevelDebug: | ||
| return "[debu]" | ||
| case slog.LevelInfo: | ||
| return "[info]" | ||
| case slog.LevelWarn: | ||
| return "[warn]" | ||
| case slog.LevelError: | ||
| return "[erro]" | ||
| case slog.LevelCritical: | ||
| return "[crit]" | ||
| case slog.LevelFatal: | ||
| return "[fata]" | ||
| default: | ||
| return "[unkn]" | ||
| } | ||
| } |
Signed-off-by: Callum Styan <callumstyan@gmail.com>
…only saves ~1 byte per op) Signed-off-by: Callum Styan <callumstyan@gmail.com>
Emyrk
approved these changes
Nov 19, 2025
dannykopping
approved these changes
Nov 20, 2025
internal/entryhuman/entry.go
Outdated
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| case int: | ||
| var a [20]byte | ||
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | ||
| return true, err | ||
| case int8: | ||
| var a [20]byte | ||
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | ||
| return true, err | ||
| case int16: | ||
| var a [20]byte | ||
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | ||
| return true, err | ||
| case int32: | ||
| var a [20]byte | ||
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | ||
| return true, err |
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Nit: DRY
Suggested change
| case int: | |
| var a [20]byte | |
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | |
| return true, err | |
| case int8: | |
| var a [20]byte | |
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | |
| return true, err | |
| case int16: | |
| var a [20]byte | |
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | |
| return true, err | |
| case int32: | |
| var a [20]byte | |
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | |
| return true, err | |
| case int, int8, int16, int32: | |
| var a [20]byte | |
| _, err := w.Write(strconv.AppendInt(a[:0], int64(x), 10)) | |
| return true, err |
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unfortunately we can't do it quite like this, the compiler still treats each type as distinct even if they're all in the same case like this, which means we'd either have to type assert OR reflect within the case itself
we can at least move the byte slice declaration, write call, and return, into reusable writeSignedInt and writeUnsignedInt functions
Signed-off-by: Callum Styan <callumstyan@gmail.com>
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I was poking around in profiling data for our dogfood instance and I noticed that over a 24h period debug logging through the human readable log sink was producing 10-12% of our memory allocation. Garbage collection is only ~7.5% of our CPU time, but hopefully this has a nice reduction for allocs/memory allocated and small reduction for GC related CPU usage.
Benchmark data:
Note that the existing benchmark didn't cover many use cases, so the changes are not as obvious there:
Current alloc space:
Current alloc object:
Alloc objects path:
Alloc space path:
GC CPU time:
