>
> diff --git a/src/util/virfile.c b/src/util/virfile.c
> index a04f888e06..fdacd17890 100644
> --- a/src/util/virfile.c
> +++ b/src/util/virfile.c
> @@ -282,6 +282,18 @@ virFileWrapperFdNew(int *fd, const char *name, unsigned int flags)
>
> ret->cmd = virCommandNewArgList(iohelper_path, name, NULL);
>
> + if (flags & VIR_FILE_WRAPPER_BIG_PIPE) {
> + /*
> + * virsh save/resume would slow to a crawl with a default pipe size (usually 64k).
> + * This improves the situation by 400%, although going through io_helper still incurs
> + * in a performance penalty compared with a direct qemu migration to a socket.
> + */
> + int pipe_sz, rv = virFileReadValueInt(&pipe_sz, "/proc/sys/fs/pipe-max-size");
> + if (rv != 0) {
> + pipe_sz = 1024 * 1024; /* common default for pipe-max-size */
> + }
> + fcntl(pipefd[output ? 0 : 1], F_SETPIPE_SZ, pipe_sz);
> + }
I believe this entire hunk of code should be ifdef'd within #ifdef
__linux__. non-windows does not necessarily mean only linux.
