Translog Settings

Elastic Stack Elasticsearch
1

It would be helpful if I get clarification on below items

  1. Translog Settings
    We have four flush settings. For ex, I set flush to happen every 50000 operations in index.translog.flush_threshold_ops, but once 5000 operations are done with, it reaches the default of 512MB (Hypothetically) -which one takes precedence?

  2. "Elasticsearch will only report success of an index, delete, update, or bulk request to the client after the transaction log has been successfully fsynced and committed on the primary and on every allocated replica." If the index.translog.durability is default (request), what is the impact of other settings as it is supposed to sync to disk

  3. refresh_interval:-1. If this is set for all the indice, should a flush is mandated? If yes, what is the effect of other translog parameters? Also, if I don't flush is the data not queriable at any later time?

Trying to understand the behavior of Translog, Index RefreshInterval, Actual Storage search etc. Is there a workflow that can explain the overall behavior from Indexing till the data is actually stored in Index and available for searching + the parameters that affect each transition in the workflow.

2
  1. It's whatever one is reached first.
  2. Are you asking what happens if you change the defaults so it doesn't do this write-on-operation?
  3. A flush is not a refresh. Have a look at https://www.elastic.co/guide/en/elasticsearch/guide/master/translog.html