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49 lines
923 B
Markdown
49 lines
923 B
Markdown
# Object Pool Pattern
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The object pool creational design pattern is used to prepare and keep multiple
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instances according to the demand expectation.
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## Implementation
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```go
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package pool
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type Pool chan *Object
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func New(total int) *Pool {
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p := make(Pool, total)
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for i := 0; i < total; i++ {
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p <- new(Object)
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}
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return &p
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}
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```
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## Usage
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Given below is a simple lifecycle example on an object pool.
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```go
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p := pool.New(2)
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select {
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case obj := <-p:
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obj.Do( /*...*/ )
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p <- obj
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default:
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// No more objects left — retry later or fail
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return
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}
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```
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## Rules of Thumb
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- Object pool pattern is useful in cases where object initialization is more
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expensive than the object maintenance.
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- If there are spikes in demand as opposed to a steady demand, the maintenance
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overhead might overweigh the benefits of an object pool.
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- It has positive effects on performance due to objects being initialized beforehand.
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