[feature] simpler cache size configuration (#2051)

* add automatic cache max size generation based on ratios of a singular fixed memory target

Signed-off-by: kim <grufwub@gmail.com>

* remove now-unused cache max-size config variables

Signed-off-by: kim <grufwub@gmail.com>

* slight ratio tweak

Signed-off-by: kim <grufwub@gmail.com>

* remove unused visibility config var

Signed-off-by: kim <grufwub@gmail.com>

* add secret little ratio config trick

Signed-off-by: kim <grufwub@gmail.com>

* fixed a word

Signed-off-by: kim <grufwub@gmail.com>

* update cache library to remove use of TTL in result caches + slice cache

Signed-off-by: kim <grufwub@gmail.com>

* update other cache usages to use correct interface

Signed-off-by: kim <grufwub@gmail.com>

* update example config to explain the cache memory target

Signed-off-by: kim <grufwub@gmail.com>

* update env parsing test with new config values

Signed-off-by: kim <grufwub@gmail.com>

* do some ratio twiddling

Signed-off-by: kim <grufwub@gmail.com>

* add missing header

* update envparsing with latest defaults

Signed-off-by: kim <grufwub@gmail.com>

* update size calculations to take into account result cache, simple cache and extra map overheads

Signed-off-by: kim <grufwub@gmail.com>

* tweak the ratios some more

Signed-off-by: kim <grufwub@gmail.com>

* more nan rampaging

Signed-off-by: kim <grufwub@gmail.com>

* fix envparsing script

Signed-off-by: kim <grufwub@gmail.com>

* update cache library, add sweep function to keep caches trim

Signed-off-by: kim <grufwub@gmail.com>

* sweep caches once a minute

Signed-off-by: kim <grufwub@gmail.com>

* add a regular job to sweep caches and keep under 80% utilisation

Signed-off-by: kim <grufwub@gmail.com>

* remove dead code

Signed-off-by: kim <grufwub@gmail.com>

* add new size library used to libraries section of readme

Signed-off-by: kim <grufwub@gmail.com>

* add better explanations for the mem-ratio numbers

Signed-off-by: kim <grufwub@gmail.com>

* update go-cache

Signed-off-by: kim <grufwub@gmail.com>

* library version bump

Signed-off-by: kim <grufwub@gmail.com>

* update cache.result{} size model estimation

Signed-off-by: kim <grufwub@gmail.com>

---------

Signed-off-by: kim <grufwub@gmail.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/internal/cache/cache.go b/internal/cache/cache.go
index e97dce6f9..cb5503a84 100644
--- a/internal/cache/cache.go
+++ b/internal/cache/cache.go
@@ -204,3 +204,36 @@ func (c *Caches) setuphooks() {
 		c.Visibility.Invalidate("RequesterID", user.AccountID)
 	})
 }
+
+// Sweep will sweep all the available caches to ensure none
+// are above threshold percent full to their total capacity.
+//
+// This helps with cache performance, as a full cache will
+// require an eviction on every single write, which adds
+// significant overhead to all cache writes.
+func (c *Caches) Sweep(threshold float64) {
+	c.GTS.Account().Trim(threshold)
+	c.GTS.AccountNote().Trim(threshold)
+	c.GTS.Block().Trim(threshold)
+	c.GTS.BlockIDs().Trim(threshold)
+	c.GTS.Emoji().Trim(threshold)
+	c.GTS.EmojiCategory().Trim(threshold)
+	c.GTS.Follow().Trim(threshold)
+	c.GTS.FollowIDs().Trim(threshold)
+	c.GTS.FollowRequest().Trim(threshold)
+	c.GTS.FollowRequestIDs().Trim(threshold)
+	c.GTS.Instance().Trim(threshold)
+	c.GTS.List().Trim(threshold)
+	c.GTS.ListEntry().Trim(threshold)
+	c.GTS.Marker().Trim(threshold)
+	c.GTS.Media().Trim(threshold)
+	c.GTS.Mention().Trim(threshold)
+	c.GTS.Notification().Trim(threshold)
+	c.GTS.Report().Trim(threshold)
+	c.GTS.Status().Trim(threshold)
+	c.GTS.StatusFave().Trim(threshold)
+	c.GTS.Tag().Trim(threshold)
+	c.GTS.Tombstone().Trim(threshold)
+	c.GTS.User().Trim(threshold)
+	c.Visibility.Trim(threshold)
+}