Hi Richard, hi list, I got around to devote some time to my patchsets and while working on my ubd block read one, I observed the following behaviour with stock 4.8.0-rc7
On a freshly booted image, stock 4.8.0-rc7, Debian jessie userspace: root@wyvern-uml:~# while true; do dd if=/dev/ubda of=/dev/null bs=1M ; done 4096+0 records in 4096+0 records out 4294967296 bytes (4.3 GB) copied, 8.14403 s, 527 MB/s 4096+0 records in 4096+0 records out 4294967296 bytes (4.3 GB) copied, 9.52683 s, 451 MB/s 4096+0 records in 4096+0 records out 4294967296 bytes (4.3 GB) copied, 10.1613 s, 423 MB/s 4096+0 records in 4096+0 records out 4294967296 bytes (4.3 GB) copied, 10.2111 s, 421 MB/s This gets progressively worse until it reaches about 380MB/s in 5-10 more runs. The rate at which it slows down decreases overtime. A. ------------------------------------------------------------------------------ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
