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Diffstat (limited to 'pkg/sentry/fsmetric/fsmetric.go')
| -rw-r--r-- | pkg/sentry/fsmetric/fsmetric.go | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/pkg/sentry/fsmetric/fsmetric.go b/pkg/sentry/fsmetric/fsmetric.go new file mode 100644 index 000000000..7e535b527 --- /dev/null +++ b/pkg/sentry/fsmetric/fsmetric.go @@ -0,0 +1,83 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package fsmetric defines filesystem metrics that are used by both VFS1 and +// VFS2. +// +// TODO(gvisor.dev/issue/1624): Once VFS1 is deleted, inline these metrics into +// VFS2. +package fsmetric + +import ( + "time" + + "gvisor.dev/gvisor/pkg/metric" +) + +// RecordWaitTime enables the ReadWait, GoferReadWait9P, GoferReadWaitHost, and +// TmpfsReadWait metrics. Enabling this comes at a CPU cost due to performing +// three clock reads per read call. +// +// Note that this is only performed in the direct read path, and may not be +// consistently applied for other forms of reads, such as splice. +var RecordWaitTime = false + +// Metrics that apply to all filesystems. +var ( + Opens = metric.MustCreateNewUint64Metric("/fs/opens", false /* sync */, "Number of file opens.") + Reads = metric.MustCreateNewUint64Metric("/fs/reads", false /* sync */, "Number of file reads.") + ReadWait = metric.MustCreateNewUint64NanosecondsMetric("/fs/read_wait", false /* sync */, "Time waiting on file reads, in nanoseconds.") +) + +// Metrics that only apply to fs/gofer and fsimpl/gofer. +var ( + GoferOpensWX = metric.MustCreateNewUint64Metric("/gofer/opened_write_execute_file", true /* sync */, "Number of times a executable file was opened writably from a gofer.") + GoferOpens9P = metric.MustCreateNewUint64Metric("/gofer/opens_9p", false /* sync */, "Number of times a file was opened from a gofer and did not have a host file descriptor.") + GoferOpensHost = metric.MustCreateNewUint64Metric("/gofer/opens_host", false /* sync */, "Number of times a file was opened from a gofer and did have a host file descriptor.") + GoferReads9P = metric.MustCreateNewUint64Metric("/gofer/reads_9p", false /* sync */, "Number of 9P file reads from a gofer.") + GoferReadWait9P = metric.MustCreateNewUint64NanosecondsMetric("/gofer/read_wait_9p", false /* sync */, "Time waiting on 9P file reads from a gofer, in nanoseconds.") + GoferReadsHost = metric.MustCreateNewUint64Metric("/gofer/reads_host", false /* sync */, "Number of host file reads from a gofer.") + GoferReadWaitHost = metric.MustCreateNewUint64NanosecondsMetric("/gofer/read_wait_host", false /* sync */, "Time waiting on host file reads from a gofer, in nanoseconds.") +) + +// Metrics that only apply to fs/tmpfs and fsimpl/tmpfs. +var ( + TmpfsOpensRO = metric.MustCreateNewUint64Metric("/in_memory_file/opens_ro", false /* sync */, "Number of times an in-memory file was opened in read-only mode.") + TmpfsOpensW = metric.MustCreateNewUint64Metric("/in_memory_file/opens_w", false /* sync */, "Number of times an in-memory file was opened in write mode.") + TmpfsReads = metric.MustCreateNewUint64Metric("/in_memory_file/reads", false /* sync */, "Number of in-memory file reads.") + TmpfsReadWait = metric.MustCreateNewUint64NanosecondsMetric("/in_memory_file/read_wait", false /* sync */, "Time waiting on in-memory file reads, in nanoseconds.") +) + +// StartReadWait indicates the beginning of a file read. +func StartReadWait() time.Time { + if !RecordWaitTime { + return time.Time{} + } + return time.Now() +} + +// FinishReadWait indicates the end of a file read whose time is accounted by +// m. start must be the value returned by the corresponding call to +// StartReadWait. +// +// FinishReadWait is marked nosplit for performance since it's often called +// from defer statements, which prevents it from being inlined +// (https://github.com/golang/go/issues/38471). +//go:nosplit +func FinishReadWait(m *metric.Uint64Metric, start time.Time) { + if !RecordWaitTime { + return + } + m.IncrementBy(uint64(time.Since(start).Nanoseconds())) +} |