article thumbnail

SQL Server on Linux: Scatter/Gather == Vectored I/O

SQL Server According to Bob

On Linux the total number of buffers that can be read or written, in a single ABI request, is capped at 2048. The buffers must be the operating system page size (4K.) Within LibOS, when we detect a request exceeding 2048 OS pages, we split the request into multiple 2048 page chunks, deemed sub-I/O requests.

Servers 40
article thumbnail

SQL Server I/O Basics Chapter #2

SQL Server According to Bob

Subsystem / Path The ​​ I/O subsystem or path ​​ includes ​​ those ​​ components ​​ that are ​​ used to support an I/O operation. ​​ SQL Server ​​ copy-on-write actions are used to maintain snapshot databases in SQL Server 2005.

Servers 40