Virtual Cache
Virtual cache represent the cache nodes detected by server agents' plugins. The performance metrics of the cache are also from the Cache client-side perspective.
For example, Redis plugins in the Java agent could detect the latency of command As a result, SkyWalking would show traffic, latency, success rate, and sampled slow operations(write/read) powered by backend analysis capabilities in this dashboard.
The cache operation span should have
- It is an Exit or Local span
- Span’s layer == CACHE
- Tag key =
cache.type
, value = The type of cache system , e.g. redis - Tag key =
cache.op
, value =read
orwrite
, indicates the value of tagcache.cmd
is used forwrite
orread
operation - Tag key =
cache.cmd
, value = the cache command , e.g. get,set,del - Tag key =
cache.key
, value = the cache key - If the cache system is in-memory (e.g. Guava-cache), agents' plugin would create a local span usually, and the span’s peer would be null ,otherwise the peer is the network address(IP or domain) of Cache server.
Ref slow cache doc to know more slow Cache commands settings.