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e9eda7e7c8
* cache: add sharded cache implementation Add Cache impl and a few tests. This cache is 256-way sharded, mainly so each shard has it's own lock. The main cache structure is a readonly jump plane into the right shard. This should remove the single lock contention on the main lock and provide more concurrent throughput - Obviously this hasn't been tested or measured. The key into the cache was made a uint32 (hash.fnv) and the hashing op is not using strings.ToLower anymore remove any GC in that code path. * here too * Minimum shard size * typos * blurp * small cleanups no defer * typo * Add freq based on Johns idea * cherry-pick conflict resolv * typo * update from early code review from john * add prefetch to the cache * mw/cache: add prefetch * remove println * remove comment * Fix tests * Test prefetch in setup * Add start of cache * try add diff cache options * Add hacky testcase * not needed * allow the use of a percentage for prefetch If the TTL falls below xx% do a prefetch, if the record was popular. Some other fixes and correctly prefetch only popular records.
55 lines
1.2 KiB
Go
55 lines
1.2 KiB
Go
// Package freq keeps track of last X seen events. The events themselves are not stored
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// here. So the Freq type should be added next to the thing it is tracking.
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package freq
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import (
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"sync"
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"time"
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)
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type Freq struct {
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// Last time we saw a query for this element.
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last time.Time
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// Number of this in the last time slice.
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hits int
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sync.RWMutex
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}
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// New returns a new initialized Freq.
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func New(t time.Time) *Freq {
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return &Freq{last: t, hits: 0}
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}
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// Updates updates the number of hits. Last time seen will be set to now.
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// If the last time we've seen this entity is within now - d, we increment hits, otherwise
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// we reset hits to 1. It returns the number of hits.
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func (f *Freq) Update(d time.Duration, now time.Time) int {
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earliest := now.Add(-1 * d)
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f.Lock()
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defer f.Unlock()
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if f.last.Before(earliest) {
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f.last = now
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f.hits = 1
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return f.hits
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}
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f.last = now
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f.hits++
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return f.hits
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}
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// Hits returns the number of hits that we have seen, according to the updates we have done to f.
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func (f *Freq) Hits() int {
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f.RLock()
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defer f.RUnlock()
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return f.hits
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}
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// Reset resets f to time t and hits to hits.
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func (f *Freq) Reset(t time.Time, hits int) {
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f.Lock()
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defer f.Unlock()
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f.last = t
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f.hits = hits
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}
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