Re: [Libguestfs] [PATCH libnbd 3/3] examples: copy-libev.c: Support extents

On Mon, Mar 08, 2021 at 01:26:44AM +0200, Nir Soffer wrote: > $ strace -f -c ../copy/nbdcopy --sparse=1048576 --request-size=1048576 > --requests=16 --connections=1 $SRC $DST > strace: Process 1094611 attached > strace: Process 1094612 attached > strace: Process 1094613 attached > strace: Process 1094614 attached > strace: Process 1094615 attached > strace: Process 1094616 attached > strace: Process 1094617 attached > strace: Process 1094618 attached > strace: Process 1094619 attached > strace: Process 1094620 attached > strace: Process 1094621 attached > strace: Process 1094622 attached > strace: Process 1094623 attached > strace: Process 1094641 attached > > (Not sure why we start so many threads with --connections=1 - bug?) I'm not sure of the exact command, so I used: $ ./run nbdcopy --sparse=1048576 --request-size=1048576 --requests=16 --connections=1 -- [ qemu-nbd -f qcow2 -t ~/fedora-32.qcow2 ] [ nbdkit memory 6G ] Temporarily adding -v shows: nbdcopy: src: nbd_ops "qemu-nbd" nbdcopy: src: size=6442450944 nbdcopy: dst: nbd_ops "nbdkit" nbdcopy: dst: size=6442450944 nbdcopy: connections=1 requests=16 threads=1 synchronous=false ^^^^^^^^^ Many threads were created but they all appeared to be associated with the ./run script, qemu-nbd and nbdkit. nbdcopy should only create one worker thread in this scenario.