From 355711821eea51c6456a31ab61d0dc2e9db034f7 Mon Sep 17 00:00:00 2001 From: Than McIntosh Date: Tue, 16 Jul 2024 19:13:47 +0000 Subject: [PATCH] cmd/internal/cov: close counter data files eagerly When reading the counter data files from a given pod, close the underlying *os.File immediately after each one is read, as opposed to using a deferred close in the loop (which will close them all at the end of the function). Doing things this way avoids running into "too many open files" when processing large clumps of counter data files. Fixes #68468. Change-Id: Ic1fe1d36c44d3f5d7318578cd18d0e65465d71d9 Reviewed-on: https://go-review.googlesource.com/c/go/+/598735 Reviewed-by: Cherry Mui LUCI-TryBot-Result: Go LUCI --- src/cmd/internal/cov/readcovdata.go | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/src/cmd/internal/cov/readcovdata.go b/src/cmd/internal/cov/readcovdata.go index 086be40e90..e0e0634459 100644 --- a/src/cmd/internal/cov/readcovdata.go +++ b/src/cmd/internal/cov/readcovdata.go @@ -204,15 +204,12 @@ func (r *CovDataReader) visitPod(p pods.Pod) error { } r.vis.VisitMetaDataFile(p.MetaFile, mfr) - // Read counter data files. - for k, cdf := range p.CounterDataFiles { + processCounterDataFile := func(cdf string, k int) error { cf, err := os.Open(cdf) if err != nil { return r.fatal("opening counter data file %s: %s", cdf, err) } - defer func(f *os.File) { - f.Close() - }(cf) + defer cf.Close() var mr *MReader mr, err = NewMreader(cf) if err != nil { @@ -236,6 +233,14 @@ func (r *CovDataReader) visitPod(p pods.Pod) error { r.vis.VisitFuncCounterData(data) } r.vis.EndCounterDataFile(cdf, cdr, p.Origins[k]) + return nil + } + + // Read counter data files. + for k, cdf := range p.CounterDataFiles { + if err := processCounterDataFile(cdf, k); err != nil { + return err + } } r.vis.EndCounters() -- 2.48.1