Hi Mohan, this parameter provide significant improvement in big file access/write: -------------------------------------------------------------------------------------------- VirtFS on /srv/shared type 9p (rw,trans=virtio,version=9p2000.L,msize=262144)
$ dd if=/dev/zero of=test count=100000 bs=16384 100000+0 records in 100000+0 records out 1638400000 bytes (1.6 GB) copied, 36.3589 s, 45.1 MB/s l$ dd if=/dev/zero of=test count=100000 100000+0 records in 100000+0 records out 51200000 bytes (51 MB) copied, 25.6597 s, 2.0 MB/s $ dd if=/dev/zero of=test count=1024 bs=262144 1024+0 records in 1024+0 records out 268435456 bytes (268 MB) copied, 3.41936 s, 78.5 MB/s Speed of copy for large file ~45MB/s (read and write from the same disk). --------------------------------------------------------------------------------------------- But Host: time ls -lahs bam.unsorted/ many files: real 0m0.053s user 0m0.004s sys 0m0.036s VM: real 0m4.449s user 0m0.012s sys 0m0.136s -------------------------------------------------------- So we have delays on the first file access. Is it possible to resolve this issue? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/965867 Title: 9p virtual file system on qemu slow To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/965867/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
