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  1. Couchbase Server
  2. MB-59842

[Ephemeral] The 'raw' high/low-water mark are not used in item paging.

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    Description

      Steps to reproduce

      1. Created a 4 node kv cluster
      2. Created a ephemeral bucket with 1 replica and eviction=nru_eviction
      3. Loaded 20000 items onto the bucket using cbc-pillowfight
      4. Increased number of replicas to 2
      5. Rebalanced the cluster 

      Observing the following

      When number of replicas is 1, active items =20k, data total ram used = 156MB as indicated in the dashboard graphs below

       

      When replica count is increased to 2, the items get ejected/deleted and the active items reduce to 11.3k items

       

       

      The items are getting ejected even when the total ram used is around 50% the low watermark when the number of replicas are increased

      Subsequently also observing further writes being rejected/auto-deleted. The ep_total_del_items stat from cbstats increases when documents are loaded using sdk/cbc-pillowfight

       

      This behaviour is not observed in Couchbase Enterprise Edition build 7.6.0-1741.

      The behaviour is very consistently observed from Couchbase Enterprise Edition build 7.6.0-1742 to Couchbase Enterprise Edition build 7.6.0-1855

      Looks like a regression caused by MB-59368

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. DOC-11685 Ejection documentation should call out ephemeral differences

          • Major - Major loss of function.
          • Open
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              Pramada.Kolichala Pramada Kolichala
              raghav.sk Raghav S K
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              Dates

                Created:
                Updated:

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