Your SSD lies and that's ok .. I think
fsync is a linux system call that flushes all pages and metadata for a given file to the disk. It is indeed an expensive operation but required for durability especially for database systems. Regular writes that make it to the disk controller are often placed in the SSD local cache to accumulate more writes before getting flushed to the NAND cells.
However when the disk controller receives this flush command it is required to immediately persist all of the data to the NAND cells.
Some SSDs however don't do that because they don't trust the host and no-op the fsync, in some cases SSD buffers…
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Chapters (17)
Intro
1:00
A Write doesn’t write
2:00
File System Page Cache
6:00
Fsync
7:30
SSD Cache
9:20
SSD ignores the flush
9:30
15 Year old Firefox fsync bug
12:30
What happens if SSD loses power
15:00
What options does Postgres exposes?
15:30
open_sync (O_SYNC)
16:15
open_datasync (O_DSYNC)
17:10
O_DIRECT
19:00
fsync
20:50
fdatasync
21:13
fsync = off
23:30
Don’t make your API simple
26:00
Database on metal?
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Learn Programming with VB.NET - 01 - Getting Started
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Learn Programming with VB.NET - 03 - Classes and Objects (Part 2)
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Learn Programming with VB.NET - 04 - User Interface
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Learn Programming with VB.NET - 05 - By Value v. By Reference
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Learn Programming with VB.NET - 06 - Variable size, 32 bit vs 64 bit
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Learn Programming with VB.NET - 07 - Conditional Statements
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Learn Programming with VB.NET - 08 - Inheritance
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Learn Programming with VB.NET - 09 - Strategy Design Pattern
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Learn Programming with VB.NET - 10 - How did I learn programming
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IGeometry 2016 Retrospective - Channel Update
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I wish I can change the name of this book
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git by Example - (IG) - #1 - Getting Started!
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git by Example - (IG) - #2 - Branches
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I Wrote Bad Front-End Code That Broke Chrome
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Content Persistence: Examples from Siri, Whatsapp and Twitter
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DeepCamp AI