[
https://issues.apache.org/jira/browse/HBASE-30107?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Vladimir Rodionov updated HBASE-30107:
--------------------------------------
Description:
h2. Description
Add metrics and observability for *cache admission decisions* and *tiered cache
topology* as part of the pluggable block cache architecture.
This change introduces metrics that make cache behavior easier to understand
and tune by exposing how blocks are admitted, rejected, placed, promoted,
demoted, and invalidated across cache tiers.
h2. Scope
* Add metrics for admission control, including:
** admitted blocks
** rejected blocks
** rejection reasons
** admission counts by source (e.g. read miss, write path, prefetch,
compaction, promotion)
* Add metrics for tiered topology behavior, including:
** L1 hits and misses
** L2 hits and misses
** promotions from L2 to L1
** demotions / removals across tiers
** invalidation counts
** per-tier capacity and usage
* Expose metrics through existing HBase metrics / JMX mechanisms where
appropriate
* Ensure metrics work with the new abstractions:
** CacheAccessService
** CacheTopology
** CachePlacementPolicy
** CacheEngine
h2. Notes
* No behavior change intended
* This ticket is focused on observability only
* Metrics should preserve compatibility with existing HBase metrics where
possible
* New metrics should help answer questions such as:
** why blocks are being rejected
** whether cache pollution is occurring
** how effectively L1 and L2 are being used
** how much promotion / demotion activity is happening
* This ticket should follow introduction of:
** CachePlacementPolicy / admission control
** CacheTopology
** CacheEngine-based cache implementations
> Add metrics for admission decisions and tiered cache topology
> -------------------------------------------------------------
>
> Key: HBASE-30107
> URL: https://issues.apache.org/jira/browse/HBASE-30107
> Project: HBase
> Issue Type: New Feature
> Components: BlockCache, Performance
> Reporter: Vladimir Rodionov
> Assignee: Vladimir Rodionov
> Priority: Major
>
> h2. Description
> Add metrics and observability for *cache admission decisions* and *tiered
> cache topology* as part of the pluggable block cache architecture.
> This change introduces metrics that make cache behavior easier to understand
> and tune by exposing how blocks are admitted, rejected, placed, promoted,
> demoted, and invalidated across cache tiers.
> h2. Scope
> * Add metrics for admission control, including:
> ** admitted blocks
> ** rejected blocks
> ** rejection reasons
> ** admission counts by source (e.g. read miss, write path, prefetch,
> compaction, promotion)
> * Add metrics for tiered topology behavior, including:
> ** L1 hits and misses
> ** L2 hits and misses
> ** promotions from L2 to L1
> ** demotions / removals across tiers
> ** invalidation counts
> ** per-tier capacity and usage
> * Expose metrics through existing HBase metrics / JMX mechanisms where
> appropriate
> * Ensure metrics work with the new abstractions:
> ** CacheAccessService
> ** CacheTopology
> ** CachePlacementPolicy
> ** CacheEngine
> h2. Notes
> * No behavior change intended
> * This ticket is focused on observability only
> * Metrics should preserve compatibility with existing HBase metrics where
> possible
> * New metrics should help answer questions such as:
> ** why blocks are being rejected
> ** whether cache pollution is occurring
> ** how effectively L1 and L2 are being used
> ** how much promotion / demotion activity is happening
> * This ticket should follow introduction of:
> ** CachePlacementPolicy / admission control
> ** CacheTopology
> ** CacheEngine-based cache implementations
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
