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From:Mauritz Sundell Date:March 5 2018 9:24am
Subject:Re: Out of operation records in local data manager far below
MaxNoOfConcurrentOperations
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Hi Hendrik

On 2018-03-05 09:03, Hendrik Woltersdorf wrote:
> Hi,
>
> we run a MySQL-Cluster, currently version 7.4.15, where we get "Out of
> operation records in local data manager" at approximately 55000 rows
> updated or deleted in one transaction,
> even though MaxNoOfConcurrentOperations=300000.
>
> Any ideas, why 300000 operation records are not enough for 55000 rows?
Assuming there are no other concurrent transactions, this could be due 
to extra implied load such as:

1) changes to unique indexes, each change takes an operation.

2) changes to blob columns, each change column can take one or more 
operation depending  on size of value.

3) foreign keys causing lookups in parent table

4) foreign keys cascading into child tables

Or it could be due to skew load due to:

5) Partial primary key used as partitioning key.

6) The number of partitions do not match number of LDM-threads.
     This should typically not happen unless explicitly expressed, or if 
one have reconfigured cluster with more LDM-threads or adding nodes 
without runnning reorganize partitions.

One can also configure the number of operations records in local data 
manager (LDM) with MaxNoOfLocalOperations.
By default that is slightly bigger than MaxNoOfConcurrentOperation.

Mauritz

Thread
Out of operation records in local data manager far belowMaxNoOfConcurrentOperationsHendrik Woltersdorf5 Mar
  • Re: Out of operation records in local data manager far belowMaxNoOfConcurrentOperationsMauritz Sundell5 Mar
    • Antwort: Re: Out of operation records in local data manager far belowMaxNoOfConcurrentOperationsHendrik Woltersdorf5 Mar
      • Re: Antwort: Re: Out of operation records in local data manager farbelow MaxNoOfConcurrentOperationsMauritz Sundell5 Mar
        • Re: Antwort: Re: Out of operation records in local data manager farbelow MaxNoOfConcurrentOperationsMauritz Sundell5 Mar
    • Re: Out of operation records in local data manager far below MaxNoOfConcurrentOperationsTom Egan5 Mar
      • Antwort: Re: Out of operation records in local data manager far belowMaxNoOfConcurrentOperationsHendrik Woltersdorf5 Mar