https://bugs.winehq.org/show_bug.cgi?id=57388 --- Comment #2 from LekKit <nyandarknessgirl(a)gmail.com> --- Thank you very much, it's really a huge improvement. Here are new results: Wine 9.21 on the same host, synchronous ReadFile() with OVERLAPPED file position 512b reads: 634344.851175 IOPS, 309.738697 MB/s 4k reads: 628872.834744 IOPS, 2456.534511 MB/s 1M reads: 18620.033840 IOPS, 18620.033840 MB/s It's still slightly slower than a native version, but according to `strace` it's just doing another lseek() to conform to WinAPI properly (ReadFile()/WriteFile() seeks after buffer even with synchronous OVERLAPPED mode). That explains why it's ~2x slower for 512b/4k reads, as the syscall entry latency dominates the execution time (Mitigations enabled). A pretty good result overall, improving it further would require moving the file pointer into userspace which I'm not sure is doable for Wine at all. Best regards -- Do not reply to this email, post in Bugzilla using the above URL to reply. You are receiving this mail because: You are watching all bug changes.