Performance improvement: Drop identical repeating tasks from

[bluelu]

Some tasks can trigger expensive operations (e.g. allocating of the cluster which can take a lot of time on large clusters). (e.g. #8804)

It would be good if the master node would drop identical requests from client nodes as long as one request is still in the list, so they don't pile up?

Example:

  9931        1.3m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9737        7.1m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9951       35.2s HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9483         11m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9962       11.8s HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9654        9.1m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9354       12.1m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9719        7.8m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9702        8.4m HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9968       319ms HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 
   9957       24.2s HIGH     shard-failed ([index][7], node[ers2nQsQSVyF_1UrBODBxA], [P], s[INITIALIZING]), reason [master [master][RsK0yRjUQUyS-bQWr5lXpw][master][inet[/ip:9300]]{trendiction_scluster=NO_ROLE, data=false, service=searchdata, max_local_storage_nodes=1, trendiction_cluster=HR51, river=_none_, master=true} marked shard as initializing, but shard is marked as failed, resend shard failure] 

[bleskes]

Although it looks like these pile up they are actually executed in one go. One every the master needs to process a shard state tasks (failed or started) it drains the queue from all tasks of similar type and executes them together. This means there will also be one reroute for all them.

I'm closing this as it is already solved, albeit in a different way. Please re-open if I missed something...