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author | Christopher Speller <crspeller@gmail.com> | 2016-05-12 15:08:58 -0400 |
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committer | Christopher Speller <crspeller@gmail.com> | 2016-05-12 16:37:29 -0400 |
commit | 84d2482ddbff9564c9ad75b2d30af66e3ddfd44d (patch) | |
tree | 8bfa567d2b6381f4a996ada2deff8a16aa85a3ac /Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go | |
parent | d1efb66ad7b017f0fbfe6f0c20843b30f396e504 (diff) | |
download | chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.gz chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.bz2 chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.zip |
Updating go depencancies. Switching to go1.6 vendoring (#2949)
Diffstat (limited to 'Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go')
-rw-r--r-- | Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go | 214 |
1 files changed, 0 insertions, 214 deletions
diff --git a/Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go b/Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go deleted file mode 100644 index bd2765630..000000000 --- a/Godeps/_workspace/src/gopkg.in/throttled/throttled.v1/memstats.go +++ /dev/null @@ -1,214 +0,0 @@ -package throttled - -import ( - "net/http" - "runtime" - "sync" - "time" -) - -// Static check to ensure that memStatsLimiter implements Limiter. -var _ Limiter = (*memStatsLimiter)(nil) - -// The memStatsLimiter struct implements a limiter based on the memory statistics -// of the current process. -type memStatsLimiter struct { - thresholds *runtime.MemStats - refreshRate time.Duration - - lockStats sync.RWMutex - stats runtime.MemStats -} - -// MemStats creates a Throttler based on the memory statistics of the current process. -// Any combination of any (non-array) integer field of Go's runtime.MemStats structure -// can be used as thresholds to deny a request. -// -// As soon as one threshold value is reached, the access is denied. If the value can -// decrease, access will be allowed again once it gets back under the threshold value. -// Denied requests go through the denied handler, which may be specified on the Throttler -// and that defaults to the package-global variable DefaultDeniedHandler. -// -// Thresholds must be specified in absolute numbers (i.e. NumGC = 10 means stop once the -// NumGC reaches 10, not when the current value increments by 10), and zero values are -// ignored. -// -// The refreshRate indicates the frequency at which the process' memory stats are refreshed, -// and 0 means on each request. -// -func MemStats(thresholds *runtime.MemStats, refreshRate time.Duration) *Throttler { - return &Throttler{ - limiter: &memStatsLimiter{ - thresholds: thresholds, - refreshRate: refreshRate, - }, - } -} - -// Start initialized the limiter for execution. -func (m *memStatsLimiter) Start() { - // Make sure there is an initial MemStats reading - runtime.ReadMemStats(&m.stats) - if m.refreshRate > 0 { - go m.refresh() - } -} - -// refresh runs in a separate goroutine and refreshes the memory statistics -// at regular intervals. -func (m *memStatsLimiter) refresh() { - c := time.Tick(m.refreshRate) - for _ = range c { - m.lockStats.Lock() - runtime.ReadMemStats(&m.stats) - m.lockStats.Unlock() - } -} - -// Limit is called for each request to the throttled handler. It checks if -// the request can go through by checking the memory thresholds, and signals it -// via the returned channel. -func (m *memStatsLimiter) Limit(w http.ResponseWriter, r *http.Request) (<-chan bool, error) { - ch := make(chan bool, 1) - // Check if memory thresholds are reached - ch <- m.allow() - return ch, nil -} - -// allow compares the current memory stats with the thresholds, and returns -// false if any threshold is reached. -func (m *memStatsLimiter) allow() bool { - m.lockStats.RLock() - mem := m.stats - m.lockStats.RUnlock() - // If refreshRate == 0, then read on every request. - if m.refreshRate == 0 { - runtime.ReadMemStats(&mem) - } - ok := true - checkStat(m.thresholds.Alloc, mem.Alloc, &ok) - checkStat(m.thresholds.BuckHashSys, mem.BuckHashSys, &ok) - checkStat(m.thresholds.Frees, mem.Frees, &ok) - checkStat(m.thresholds.GCSys, mem.GCSys, &ok) - checkStat(m.thresholds.HeapAlloc, mem.HeapAlloc, &ok) - checkStat(m.thresholds.HeapIdle, mem.HeapIdle, &ok) - checkStat(m.thresholds.HeapInuse, mem.HeapInuse, &ok) - checkStat(m.thresholds.HeapObjects, mem.HeapObjects, &ok) - checkStat(m.thresholds.HeapReleased, mem.HeapReleased, &ok) - checkStat(m.thresholds.HeapSys, mem.HeapSys, &ok) - checkStat(m.thresholds.LastGC, mem.LastGC, &ok) - checkStat(m.thresholds.Lookups, mem.Lookups, &ok) - checkStat(m.thresholds.MCacheInuse, mem.MCacheInuse, &ok) - checkStat(m.thresholds.MCacheSys, mem.MCacheSys, &ok) - checkStat(m.thresholds.MSpanInuse, mem.MSpanInuse, &ok) - checkStat(m.thresholds.MSpanSys, mem.MSpanSys, &ok) - checkStat(m.thresholds.Mallocs, mem.Mallocs, &ok) - checkStat(m.thresholds.NextGC, mem.NextGC, &ok) - checkStat(uint64(m.thresholds.NumGC), uint64(mem.NumGC), &ok) - checkStat(m.thresholds.OtherSys, mem.OtherSys, &ok) - checkStat(m.thresholds.PauseTotalNs, mem.PauseTotalNs, &ok) - checkStat(m.thresholds.StackInuse, mem.StackInuse, &ok) - checkStat(m.thresholds.StackSys, mem.StackSys, &ok) - checkStat(m.thresholds.Sys, mem.Sys, &ok) - checkStat(m.thresholds.TotalAlloc, mem.TotalAlloc, &ok) - return ok -} - -// Checks the threshold value against the actual value, and assigns false -// to the boolean pointer if the threshold is reached. -func checkStat(threshold, actual uint64, ok *bool) { - if !*ok { - return - } - if threshold > 0 { - if actual >= threshold { - *ok = false - } - } -} - -// MemThresholds is a convenience function to create a thresholds memory stats from -// offsets to apply to the current memory stats. Zero values in the offset stats -// are left to 0 in the resulting thresholds memory stats value. -// -// The return value may be used as thresholds argument to the MemStats function. -func MemThresholds(offset *runtime.MemStats) *runtime.MemStats { - var mem, thr runtime.MemStats - runtime.ReadMemStats(&mem) - if offset.Alloc > 0 { - thr.Alloc = mem.Alloc + offset.Alloc - } - if offset.BuckHashSys > 0 { - thr.BuckHashSys = mem.BuckHashSys + offset.BuckHashSys - } - if offset.Frees > 0 { - thr.Frees = mem.Frees + offset.Frees - } - if offset.GCSys > 0 { - thr.GCSys = mem.GCSys + offset.GCSys - } - if offset.HeapAlloc > 0 { - thr.HeapAlloc = mem.HeapAlloc + offset.HeapAlloc - } - if offset.HeapIdle > 0 { - thr.HeapIdle = mem.HeapIdle + offset.HeapIdle - } - if offset.HeapInuse > 0 { - thr.HeapInuse = mem.HeapInuse + offset.HeapInuse - } - if offset.HeapObjects > 0 { - thr.HeapObjects = mem.HeapObjects + offset.HeapObjects - } - if offset.HeapReleased > 0 { - thr.HeapReleased = mem.HeapReleased + offset.HeapReleased - } - if offset.HeapSys > 0 { - thr.HeapSys = mem.HeapSys + offset.HeapSys - } - if offset.LastGC > 0 { - thr.LastGC = mem.LastGC + offset.LastGC - } - if offset.Lookups > 0 { - thr.Lookups = mem.Lookups + offset.Lookups - } - if offset.MCacheInuse > 0 { - thr.MCacheInuse = mem.MCacheInuse + offset.MCacheInuse - } - if offset.MCacheSys > 0 { - thr.MCacheSys = mem.MCacheSys + offset.MCacheSys - } - if offset.MSpanInuse > 0 { - thr.MSpanInuse = mem.MSpanInuse + offset.MSpanInuse - } - if offset.MSpanSys > 0 { - thr.MSpanSys = mem.MSpanSys + offset.MSpanSys - } - if offset.Mallocs > 0 { - thr.Mallocs = mem.Mallocs + offset.Mallocs - } - if offset.NextGC > 0 { - thr.NextGC = mem.NextGC + offset.NextGC - } - if offset.NumGC > 0 { - thr.NumGC = mem.NumGC + offset.NumGC - } - if offset.OtherSys > 0 { - thr.OtherSys = mem.OtherSys + offset.OtherSys - } - if offset.PauseTotalNs > 0 { - thr.PauseTotalNs = mem.PauseTotalNs + offset.PauseTotalNs - } - if offset.StackInuse > 0 { - thr.StackInuse = mem.StackInuse + offset.StackInuse - } - if offset.StackSys > 0 { - thr.StackSys = mem.StackSys + offset.StackSys - } - if offset.Sys > 0 { - thr.Sys = mem.Sys + offset.Sys - } - if offset.TotalAlloc > 0 { - thr.TotalAlloc = mem.TotalAlloc + offset.TotalAlloc - } - return &thr -} |