docker stats: assorted fixes and optimizations in rendering#6876
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thaJeztah wants to merge 5 commits intodocker:masterfrom
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docker stats: assorted fixes and optimizations in rendering#6876thaJeztah wants to merge 5 commits intodocker:masterfrom
thaJeztah wants to merge 5 commits intodocker:masterfrom
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Pull request overview
This PR refactors and optimizes docker stats rendering by centralizing stats snapshot collection and reducing string conversions during output generation, aiming to improve performance and reduce terminal flicker.
Changes:
- Added a
snapshot()method on the internalstatstracker to safely copy the tracked container list under lock. - Updated
RunStatsto render usingbytes.Buffer/io.WriteStringand to avoidbytes -> stringconversions. - Simplified
statsFormatWriteby inlining the per-entry render closure.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
cli/command/container/stats.go |
Switches rendering to byte-oriented writes and uses snapshot() to avoid holding the stats lock while building output. |
cli/command/container/stats_helpers.go |
Adds (*stats).snapshot() helper for point-in-time container list copying. |
cli/command/container/formatter_stats.go |
Minor refactor to inline the render function passed to ctx.Write. |
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Don't write lines back into the same buffer that's being read from when clearing lines; add a separate output buffer to construct the output, then write it to the CLI's output at once (to prevent terminal flicker). Relates to / introduced in cb2f95c. Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Move logic to capture a snapshot of the current stats to the stats struct. Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This code is using a `bytes.Buffer` to render the stats, before writing the results to the CLI's output. Let's try to use bytes where possible instead of converting to a string; - Use the buffer's `Write` (and `Out().Write`) to write directly to the buffer/writer where possible. - Use `io.WriteString` instead of `fmt.Printf` - Use `bytes.SplitSeq` instead of `strings.SplitSeq` Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
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| _, _ = io.WriteString(&frameBuf, "\033[J") | ||
| _, _ = dockerCLI.Out().Write(frameBuf.Bytes()) | ||
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| if len(ccStats) == 0 && !showAll { |
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I think this is dead code since we already have the same check in L325?
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docker statsto not require clearing the whole screen #5625cli/command/container: fix buffer reuse when printing stats
Don't write lines back into the same buffer that's being read from when
clearing lines; add a separate output buffer to construct the output,
then write it to the CLI's output at once (to prevent terminal flicker).
Relates to / introduced in cb2f95c.
cli/command/container: stats: add snapshot method
Move logic to capture a snapshot of the current stats to the stats struct.
cli/command/container: RunStats: rename buffer var for brevity
cli/command/container: RunStats: avoid bytes to strings conversions
This code is using a
bytes.Bufferto render the stats, before writingthe results to the CLI's output. Let's try to use bytes where possible
instead of converting to a string;
Write(andOut().Write) to write directly to thebuffer/writer where possible.
io.WriteStringinstead offmt.Printfbytes.SplitSeqinstead ofstrings.SplitSeqcli/command/container: statsFormatWrite: inline render func
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