Cache

Use cache when Fluxheim sits in front of an origin and repeated responses should be served faster.

Proxy cache example

[cache]
enabled = true
default_ttl_secs = 300
max_object_bytes = "32MiB"
status_header = "X-Cache-Status"

[cache.memory]
enabled = true
max_size_bytes = "256MiB"

[cache.disk]
enabled = true
path = "/var/cache/fluxheim/site"
max_size_bytes = "10GiB"

Cache backends

백엔드	사용할 때
`memory`	You need the fastest cache and can keep objects in RAM.
`disk`	You need cache capacity that survives process restarts.
`tiered`	hot object에는 memory를, 더 큰 capacity에는 disk를 원할 때.
`storage-bin`	변경이 많고 제한된 disk allocation을 원할 때.
`encrypted disk`	You need cache-at-rest protection for disk objects.

Route cache policy

[[vhosts.routes]]
name = "assets"
path_prefix = "/assets/"
action = "proxy"

[vhosts.routes.proxy]
upstreams = ["127.0.0.1:3000"]

[vhosts.routes.cache]
enabled = true
status_ttls = { "200" = 3600, "404" = 60 }
content_types = ["text/css", "application/javascript", "image/*"]
extensions = ["css", "js", "png", "webp", "svg"]
include_query = false
stale_while_revalidate_secs = 30
stale_if_error_secs = 120

Advanced cache controls

제어	목적
`lock`	Collapse concurrent misses so one request fills the cache.
`range.slice`	Cache fixed byte slices for large files and resumable downloads.
`peer_fill`	origin을 사용하기 전에 한 edge가 다른 edge에서 fill하도록 합니다.
`origin_protection`	압력이 높을 때 concurrent origin fill을 제한합니다.
`cache_purger`	stale disk entry를 제한된 batch로 정리합니다.

Use cache carefully

Do not cache private user pages unless the route is explicitly safe.
Keep cache keys bounded and predictable.
content가 자주 바뀌면 purge 또는 짧은 TTL을 사용하세요.
cookie, authorization, preview header, unsafe query string에서는 bypass합니다.