Package: doxygen Version: 1.8.1.2-2 DOT_NUM_THREADS = 0 means autodetect. On bare metal it does make sense to use more threads than cores, in the assumption than disk will be the bottleneck.
This can be counterproductive on VMs, I agree. I suggest you try to force it with DOT_NUM_THREADS = 1; I tried here and it seems there is only one dot process at a time. --- System information. --- Architecture: i386 Kernel: Linux 3.2.0-4-686-pae Debian Release: 7.1 500 stable-updates mi.mirror.garr.it 500 stable security.debian.org 500 stable mi.mirror.garr.it --- Package information. --- Depends (Version) | Installed ============================-+-============== libc6 (>= 2.3.6-6~) | 2.13-38 libgcc1 (>= 1:4.1.1) | 1:4.7.2-5 libstdc++6 (>= 4.1.1) | 4.7.2-5 Recommends (Version) | Installed ============================-+-=========== doxygen-latex | 1.8.1.2-2 Suggests (Version) | Installed ==========================-+-=========== doxygen-doc | 1.8.1.2-2 doxygen-gui | 1.8.1.2-2 graphviz | 2.26.3-14 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org