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caching [2022/03/28 20:01]
yves [Tile caching]
caching [2023/11/27 18:27] (current)
chris
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 ===== Caching ===== ===== Caching =====
  
-For optimal performance,​ PMA.core ​support ​both tile cache and cloud cache.+For optimal performance,​ PMA.core ​supports ​both tile cache and cloud cache.
  
-We have a strategy where cache is deleted after a retention period ​automatically ​and no new cache is created if there is not enough disk space.+Our policy ​is that caches are deleted ​automatically ​after a retention period and no new cache is created if there is not enough disk space.
  
 There'​s a [[settings_image#​cache_settings|separate configuration page for cache settings]] There'​s a [[settings_image#​cache_settings|separate configuration page for cache settings]]
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 It is impossible to load an image from cloud storage if there is no disk space. It is impossible to load an image from cloud storage if there is no disk space.
  
-Let's assume that the whole disk space is 100GB, currently consumed ​is 95GB and PMA.core is instructed not to cache if there is not at least 1GB of free space. Furthermore,​ let's assume the retention days is set to 30 and that all the cache has been created in the last 10 days.+Let's assume that the whole disk space is 100GB, ​95GB is currently consumed and PMA.core is instructed not to cache when there is less than 1GB of free space. Furthermore,​ let's assume the retention days option ​is set to 30 and that all the cache was created in the last 10 days.
  
-If now there are 10 or 100 requests to load different images, PMA.core has to cache chunks of these images and suddenly there is no space and there is nothing that can be deleted.+If 100 requests to load different images ​come in, PMA.core has to cache chunks of these imagesand suddenly there is no space and there is nothing that can be deleted.
  
-you can take this to a higher extreme and assume you have 100GB free space on a 100GB disk and you receive 100s of requests for "Image Info". This will again cause PMA.core to store chunks of 100s of images to the disk simultaneously,​ and may end up in a full disk (without breaking any rule).+You can take this to a higher extreme and assume you have 100GB of free space on a 100GB disk and you receive 100s of requests for "Image Info". This will again cause PMA.core to store chunks of 100s of images to the disk simultaneously,​ and may end up in a full disk (without breaking any rule).
  
 After this point nothing works, because PMA.core doesn'​t know what to delete; all the cache is fresh. You now have to purge the cache folder(s) manually, after which the build process may re-commence (you may also provide more storage for your cache repositories this time around). After this point nothing works, because PMA.core doesn'​t know what to delete; all the cache is fresh. You now have to purge the cache folder(s) manually, after which the build process may re-commence (you may also provide more storage for your cache repositories this time around).
caching.1648486906.txt.gz ยท Last modified: 2022/03/28 20:01 by yves