[Cache] give 100ms before starting the expiration countdown #33846
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| @@ -76,15 +76,15 @@ static function ($deferred, $namespace, &$expiredIds) use ($getId) { | |||
| $key = (string) $key; | |||
| if (null === $item->expiry) { | |||
| $ttl = 0 < $item->defaultLifetime ? $item->defaultLifetime : 0; | |||
| } elseif (0 >= $ttl = (int) ($item->expiry - $now)) { | |||
| } elseif (0 >= $ttl = (int) (0.1 + $item->expiry - $now)) { | |||
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This could look like a "magic number" in the future and people won't understand why we use it. We could add a very brief comment explaining "why" ... or we could move this to a self-explanatory private constant (e.g. self::MINIMUM_CACHE_TTL or something better).
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The value is spread in many unrelated adapters, a private constant doesn't work.
I'm not sure this deserves more honestly, git blame can tell why if anyone wonders.
nicolas-grekas
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Oct 4, 2019
…n (nicolas-grekas) This PR was merged into the 4.3 branch. Discussion ---------- [Cache] give 100ms before starting the expiration countdown | Q | A | ------------- | --- | Branch? | 4.3 | Bug fix? | yes | New feature? | no | Deprecations? | no | Tickets | Fix #31573, Fix #33837 | License | MIT | Doc PR | - Because the expiration count-down starts immediately after calling `CachItem::expiresAfter(N)`, it's impossible to actually cache items for more than `N-1` seconds. This PR adds a 0.1s grace period so that backends that have a second-level resolution can store the items for `N` seconds, provided the time between calling `CachItem::expiresAfter(N)` and saving the value to the backend is lower than 0.1s. This PR also fixes the calculation of the computation time in `ContractsTrait`. Commits ------- ba63e18 [Cache] give 100ms before starting the expiration countdown
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Because the expiration count-down starts immediately after calling
CachItem::expiresAfter(N), it's impossible to actually cache items for more thanN-1seconds.This PR adds a 0.1s grace period so that backends that have a second-level resolution can store the items for
Nseconds, provided the time between callingCachItem::expiresAfter(N)and saving the value to the backend is lower than 0.1s.This PR also fixes the calculation of the computation time in
ContractsTrait.