Hi For those interested in this topic, here is the JIRA, which has a Pull Request for review: https://issues.apache.org/jira/browse/SOLR-16954
Jan Høydahl > 3. jul. 2023 kl. 22:28 skrev Pierre Salagnac <pierre.salag...@gmail.com>: > > Hi Jan, > > As far as I know, Solr only supports circuit breaks for queries at the > moment. > > We have a custom integration of circuit breakers for indexing (in Solr 8, > so that's not fully aligned with what in solr 9) with a custom > UpdateRequestProcessor. Basically, a new instance of every update processor > is created by calling the corresponding factory. We then check system stats > (CPU...) at the first handled doc. > Maybe there are other ways of integrating circuit breakers, but at least > doing so in an update processor was not intrusive in the code. > > Probably it is worth it to have something standard in Solr. A "symetric" > class of SearchHandler to add CB integration could be UpdateRequestHandler. > > Pierre > > > Le mar. 27 juin 2023 à 13:32, Jan Høydahl <jan....@cominvent.com> a écrit : > >> Hi, >> >> Solr has CPU and Memory circuit breakers that will terminate Search >> Requests only. >> See >> https://solr.apache.org/guide/solr/latest/deployment-guide/circuit-breakers.html >> for docs. >> >> Example: >> >> <circuitBreaker class="solr.CircuitBreakerManager" enabled="true"> >> <str name="memEnabled">true</str> >> <str name="memThreshold">75</str> >> <str name="cpuEnabled">true</str> >> <str name="cpuThreshold">75</str> >> </circuitBreaker> >> >> >> A Solr node typically gets overloaded by the combined update and query >> traffic, and >> I'm looking into enabling ciricuit breakers for update requests. For many >> workloads, pausing >> update traffic would resolve the situation, with the benefit of users not >> being affected by aborted >> queries. >> >> So ideally I'd want to be able to choose to enable/disable CB on >> update/query individually. >> Or better, to kill update requests on e.g. 80% threshold and search >> requests on 90% threshold. >> >> The current breaker impl for search < >> https://github.com/apache/solr/blob/branch_9_2/solr/core/src/java/org/apache/solr/handler/component/SearchHandler.java#L372:380> >> [1] is hardcoded into SearchHandler in such a way that if ANY >> of the configured breakers trips, search requests are aborted. Also the >> breakers seem to be generic >> in nature, named CPUCircuitBreaker < >> https://github.com/apache/solr/blob/branch_9_2/solr/core/src/java/org/apache/solr/util/circuitbreaker/CPUCircuitBreaker.java> >> and MemoryCircuitBreaker < >> https://github.com/apache/solr/blob/branch_9_2/solr/core/src/java/org/apache/solr/util/circuitbreaker/MemoryCircuitBreaker.java>, >> so adding new UpdateCPUCircuitBreaker >> does not seem to be the intention here. >> >> I'm also unclear on the usefulness of having CB on the core level and not >> the node level. If you have >> 10 cores from 10 collections on a node, and only some have CBs while >> others do not, the node will >> still be overloaded unless the admin convinces every collection owner to >> implement the same CBs? >> >> So my question becomes - how do we enable CB for update requests into this >> mix in a clean way? >> >> Jan
