view TODO @ 447:5881e4af5799 pg-transactions

measure DB latency
author Alain Mazy <am@osimis.io>
date Mon, 15 Jan 2024 18:27:20 +0100
parents cec6a0cd399f
children f4244c7e2725 15e609c439d1
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== Orthanc database plugins ==
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Common - Database index
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* Performance of joins in LookupResources: Create cached statement for
  LookupResources, that are grouped to search up to, say, 10 tags,
  instead of recompiling for each request

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Common - Storage area
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* Implement the "StoreDicom" option from the default filesystem
  storage area to run MySQL/PostgreSQL storage in index-only mode:
  https://orthanc.uclouvain.be/book/contributing.html

* Performance: Add a pool of connections to PostgreSQL/MySQL, as
  already done in the database index plugins

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PostgreSQL
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* reported issue to validate:  uploading lots of files through HTTP with:
  - 1 client and IndexConnectionsCount==1 took 100s
  - 2 client and IndexConnectionsCount==2 took 600s (lots of transaction replayed)

* Seems Orthanc might deadlock when there are plenty of conflicting transactions:
  https://groups.google.com/g/orthanc-users/c/xQelEcKqL9U/m/HsvxwlkvAQAJ
  https://groups.google.com/g/orthanc-users/c/1bkClfZ0KBA/m/s4AlwVh3CQAJ 

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MySQL
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* Store revisions for metadata and attachments in MySQL (this is
  already implemented in PostgreSQL)

* MySQL performance => implement GlobalProperty_GetTotalSizeIsFast:
  https://groups.google.com/d/msg/orthanc-users/kSR4a110zDo/D7e4ITR8BwAJ

* Add index to speed up wildcard search, as already done in PostgreSQL:

  - https://dev.mysql.com/doc/refman/5.5/en/fulltext-search.html +
    ALTER TABLE table ADD FULLTEXT index_name(column1);

  - https://dev.mysql.com/doc/refman/8.0/en/index-btree-hash.html