skywalking-java/docs/en/setup/backend/backend-storage.md

Backend storage

SkyWalking storage is pluggable, we have provided the following storage solutions, you could easily use is by changing the application.yml

• H2
• ElasticSearch 6

H2

Active H2 as storage, set storage provider to H2 In-Memory Databases. Default in distribution package. Please read Database URL Overview in H2 official document, you could set the target to H2 in Embedded, Server and Mixed modes.

Setting fragment example

storage:
  h2:
    driver: org.h2.jdbcx.JdbcDataSource
    url: jdbc:h2:mem:skywalking-oap-db
    user: sa

ElasticSearch 6

Active ElasticSearch 6 as storage, set storage provider to elasticsearch.

Required ElasticSearch 6.3.0 or higher.

Setting fragment example

storage:
  elasticsearch:
    clusterNodes: localhost:9200
    indexShardsNumber: 2
    indexReplicasNumber: 0
    # Batch process setting, refer to https://www.elastic.co/guide/en/elasticsearch/client/java-api/5.5/java-docs-bulk-processor.html
    bulkActions: 2000 # Execute the bulk every 2000 requests
    bulkSize: 20 # flush the bulk every 20mb
    flushInterval: 10 # flush the bulk every 10 seconds whatever the number of requests
    concurrentRequests: 2 # the number of concurrent requests
    # Set a timeout on metric data. After the timeout has expired, the metric data will automatically be deleted.
    traceDataTTL: 90 # Unit is minute
    minuteMetricDataTTL: 90 # Unit is minute
    hourMetricDataTTL: 36 # Unit is hour
    dayMetricDataTTL: 45 # Unit is day
    monthMetricDataTTL: 18 # Unit is month

More storage solution extension

Follow Storage extension development guide in Project Extensions document in development guide.