slicebuffers_success variant tests failing sporadically

[runfoapp]

Runfo Tracking Issue: slicebuffers_success variant tests failing sporadically

Build	Definition	Kind	Run Name
996179	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1014.Amd64.Open
995307	runtime	PR 48305	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
994925	runtime	PR 48298	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
994500	runtime	PR 47950	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
994178	runtime	PR 48276	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
994166	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1014.Amd64.Open
993140	runtime	PR 48251	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
990000	runtime	PR 48160	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
990000	runtime	PR 48160	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
989340	runtime	PR 48137	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
988913	runtime	PR 47301	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
987631	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1015.Amd64.Open
987181	runtime	PR 47829	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
987075	runtime	PR 47519	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
986108	runtime	PR 47842	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
985499	runtime	PR 47938	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
982762	runtime	PR 47906	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
982059	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1015.Amd64.Open
980951	runtime	PR 47931	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
980917	runtime	PR 47769	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
980061	runtime	PR 47821	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
978549	runtime	PR 47074	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
978280	runtime	PR 47666	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
976514	runtime	PR 47618	net6.0-OSX-Debug-x64-Mono_release-OSX.1015.Amd64.Open
974140	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1014.Amd64.Open
972359	runtime	PR 47666	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
971460	runtime	Rolling	net6.0-OSX-Release-x64-Mono_release-OSX.1013.Amd64.Open
970980	runtime	PR 43954	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
970460	runtime	PR 47316	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open

Build Result Summary

Day Hit Count	Week Hit Count	Month Hit Count
0	0	0

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Issue Details

---

Runfo Tracking Issue: slicebuffers_success variant tests failing sporadically

Build	Definition	Kind	Run Name
974140	runtime	Rolling	net6.0-OSX-Release-x64-CoreCLR_release-OSX.1014.Amd64.Open
972359	runtime	PR 47666	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1014.Amd64.Open
971460	runtime	Rolling	net6.0-OSX-Release-x64-Mono_release-OSX.1013.Amd64.Open
970980	runtime	PR 43954	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open
970460	runtime	PR 47316	net6.0-OSX-Debug-x64-CoreCLR_release-OSX.1015.Amd64.Open

Build Result Summary

Day Hit Count	Week Hit Count	Month Hit Count
1	5	5

Author:	runfoapp[bot]
Assignees:	-
Labels:	area-System.Net.Sockets, untriaged
Milestone:	-

[Anipik]

Failed again https://dev.azure.com/dnceng/public/_build/results?buildId=982059&view=logs&j=05e92ac1-194e-59cf-664a-fa72d1cdd19b&t=caea1d4b-c90c-5be1-e57d-c4635079c333

[ViktorHofer]

Failed again in https://dev.azure.com/dnceng/public/_build/results?buildId=980951&view=ms.vss-test-web.build-test-results-tab&runId=30751418&resultId=136298&paneView=debug

Assert.Equal() Failure\nExpected: 100\nActual:   50
   at System.Net.Sockets.Tests.SendFile`1.SliceBuffers_Success() in /_/src/libraries/System.Net.Sockets/tests/FunctionalTests/SendFile.cs:line 226
--- End of stack trace from previous location ---

[ViktorHofer]

cc @dotnet/ncl

[geoffkizer]

@antonfirsov This is a new test, right? I suspect the underlying issue isn't new, we've just never hit it before.

Regardless, we should investigate and fix.