On Wed, Jun 11, 2025 at 12:32:58AM +0200, Dimitrios Apostolou wrote: > Thank you for benchmarking! Before answering in more depth, I'm curious, > what read-seek pattern do you see on the system call level (as shown by > strace)? In pg_restore it was a constant loop of read(4K)-lseek(8-16K).
For fseeko(), sizes less than 4096 produce a repeating pattern of read() calls followed by approximately (4096 / size) lseek() calls. For greater sizes, it's just a stream of lseek(). For fread(), sizes less than 4096 produce a stream of read(fd, "...", 4096), and for greater sizes, the only difference is that the last argument is the size. -- nathan
