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Issue Plesk constantly runs EXPLAIN queries causing high tmp disk usage – how to stop it?

kmhesaplama

New Pleskian
Server operating system version
CentOS Linux 7.9.2009 (Core)
Plesk version and microupdate number
Plesk Obsidian v18.0.69
Hi,


I noticed that on my Plesk server, a large number of EXPLAIN queries are constantly executing while performance_schema is active. All of these queries create temporary tables and write them directly to disk. As a result, the Created_tmp_disk_tables counter is skyrocketing, and my temporary disk usage is up to 98%.


EXPLAIN queries target these types of tables:


  • SchemaVersions, clients, sessions, locales, ServiceNodes, Modules, etc.

All of them perform full table scans without indexing and create disk-based temporary tables.


  • How can I prevent Plesk from running these automatic EXPLAIN queries?
  • Is adding [ext-monitoring] enabled=false to the Panel.ini file enough to stop them?
  • If I stop these queries, what features in Plesk (such as Advisor, Health Monitoring, internal statistics) will be disabled?

Any advice would be appreciated.

[courtesy admin translation]

Merhaba,


Plesk sunucumda, performance_schema etkinken sürekli olarak çok sayıda EXPLAIN sorgusunun yürütüldüğünü fark ettim. Bu sorguların hepsi geçici tablolar oluşturuyor ve bunları doğrudan diske yazıyor. Sonuç olarak, Created_tmp_disk_tables sayacı hızla artıyor ve geçici disk kullanımım %98'e kadar çıkıyor.


EXPLAIN sorguları şu tür tabloları hedefliyor:


  • SchemaVersions, istemciler, oturumlar, yerel ayarlar, ServiceNode'lar, Modüller, vb.

Hepsi indeksleme olmaksızın tam tablo taramaları gerçekleştirir ve disk tabanlı geçici tablolar oluşturur.


  • Plesk'in bu otomatik EXPLAIN sorgularını çalıştırmasını nasıl önleyebilirim?
  • Panel.ini dosyasına [ext-monitoring] enabled = false eklemek onları durdurmak için yeterli mi?
  • Bu sorguları durdurursam Plesk'teki hangi özellikler (Danışman, Sağlık İzleme, dahili istatistikler gibi) devre dışı kalacak?

Herhangi bir tavsiyeniz memnuniyetle karşılanacaktır.
 
Last edited by a moderator:
This will most likely require a review by our engineers, I would suggest opening a ticket with Plesk support for an investigation of the issue on your server. To sign-in to support and open a ticket, please go to:


If you got your license from a reseller, your reseller is responsible for handling support inquiries. They can forward the inquiry to our engineers. If the reseller does not provide support, here is an alternative to get support directly from Plesk:

 
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