connect: reduce allocations when building SET command #1111
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connection.go
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| params = append(params, param+"="+val) | ||
| if cmdSet == nil { | ||
| // Heuristic: 29 chars for each other key=value to reduce reallocations | ||
| cmdSet = make([]byte, 0, 4+len(param)+1+len(val)+30*(len(mc.cfg.Params)-1)) |
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Wouldn't it make sense to use either a const-sized buffer on the heap for the common case or try to use the mc.buf?
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A better memory saving would occur by building the SET NAMES and SET commands just once for all connections as the DSN is frozen, and store them in the connector. But this is more profound refactoring.
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#1115 is the first step to move the connection-independent parts of handleParams to a connector constructor.
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Please use strings.Builder.
https://golang.org/pkg/strings/#Builder
OK, |
|
@methane Code pushed using strings.Builder. |
dolmen
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…1111) * connect: reduce allocations when building SET command * handleParams: use strings.Builder instead of direct []byte
…1111) * connect: reduce allocations when building SET command * handleParams: use strings.Builder instead of direct []byte
Description
As a follow-up to #1099 (see #1099 (comment)), here is an improvement of the
handleParamsfunction to reduce number of allocations when building theSETcommand to set session variables.Checklist