Re: troubleshooting slow I/O performance.

From: Andy Sayer <>
Date: Wed, 09 May 2018 17:35:50 +0000
Message-ID: <>

“The real question is what do you expect from the disk subsystem?”

Arguably the real question is what do you need from the disk subsystem. Many applications will run fine with 50ms random IOs. Sure, your big batchy operations may take a few hours but so what? If your application is using sensible queries with sensible supporting indexes then your average user call will be just fine, especially when you remember that you have caches everywhere to prevent these IOs.

SLOB is very good at finding the breaking point of your storage. Your application may be no where near as “good”.

Hope that helps,

Received on Wed May 09 2018 - 19:35:50 CEST

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