-B<Important note:>
-When you use this call, the filesystem options C<sync> and C<noatime>
-are set implicitly. This was originally done because we thought it
-would improve reliability, but it turns out that I<-o sync> has a
-very large negative performance impact and negligible effect on
-reliability. Therefore we recommend that you avoid using
-C<guestfs_mount> in any code that needs performance, and instead
-use C<guestfs_mount_options> (use an empty string for the first
-parameter if you don't want any options).");
+Before libguestfs 1.13.16, this call implicitly added the options
+C<sync> and C<noatime>. The C<sync> option greatly slowed
+writes and caused many problems for users. If your program
+might need to work with older versions of libguestfs, use
+C<guestfs_mount_options> instead (using an empty string for the
+first parameter if you don't want any options).");