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Trace Flag 8904 - Disable Inline Database Log Flushes

BobDorr's avatar
BobDorr
Icon for Microsoft rankMicrosoft
Dec 12, 2022
A log cache block holds log records for the database. Many workers are allowed to add log records to the same log cache buffer (LC) in parallel.  When the log cache block becomes full, or a commit re...
Updated Dec 12, 2022
Version 2.0
bobsql
sqlserverperformance
Pankaj_Mittal's avatar
Pankaj_Mittal
Copper Contributor
May 29, 2025

Hello BobDorr​ : We are utilizing this TF 8904 for some of our largest customers since we were running into this same issue. We are in the process of upgrading our SQL instances from SQL 2019 to SQL 2022. we would like to keep the TF on even in SQL 2022 just to avoid any possibility of the impact. I know SQL Server 2022 addresses this issue with an enhanced automatic feature that detects when inline log I/O is detrimental to performance and disable it. But is that enhancement a total replacement for TF 8904? Does TF8904 even have any impact at all in SQL Server 2022?