Re: [Libguestfs] [PATCH 2/2] actions: refactor available & feature_available
On Thu, Nov 05, 2015 at 04:56:43PM +0100, Pino Toscano wrote:
Refactor the internal_feature_available to return the result for
just
one group, so it is easier to know on the library side what was the
actual error, and which group refers to; drop internal_available, as no
more needed after this.
On the library side, implement in available and feature_available the
real logic to iterate through the requested group, and error out or
return whether the groups are available. This also introduces caching
for the features, so each needs to be queried just once in each
appliance run.
The result of this is that there should be much less communication with
the daemon to know about available features; the downside is that
queries for more than one group at once, not already cached, will be
cause more queries to the daemon.
This commit causes the following valgrind failures. Curiously they
only occur in virt-v2v:
==25905== HEAP SUMMARY:
==25905== in use at exit: 3,604,364 bytes in 1,663 blocks
==25905== total heap usage: 83,930 allocs, 82,267 frees, 4,200,256,957 bytes allocated
==25905==
==25905== 41 (32 direct, 9 indirect) bytes in 1 blocks are definitely lost in loss record
696 of 775
==25905== at 0x4C2AB9D: realloc (in
/usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==25905== by 0x4ECF846: guestfs_int_safe_realloc (alloc.c:80)
==25905== by 0x4ED05FF: find_or_cache_feature (available.c:48)
==25905== by 0x4ED073C: guestfs_impl_feature_available (available.c:89)
==25905== by 0x4EA4B21: guestfs_feature_available (actions-5.c:1131)
==25905== by 0x4EF9FDF: guestfs_impl_list_filesystems (listfs.c:49)
==25905== by 0x4E7EDF2: guestfs_list_filesystems (actions-3.c:419)
==25905== by 0x4EE0FD2: guestfs_impl_inspect_os (inspect.c:62)
==25905== by 0x4E50E12: guestfs_inspect_os (actions-0.c:500)
==25905== by 0x4E3292: ocaml_guestfs_inspect_os (guestfs-c-actions.c:9385)
==25905== by 0x4696C8: camlGuestfs__fun_16039 (guestfs.ml:1242)
==25905== by 0x423224: camlV2v__inspect_source_1085 (v2v.ml:306)
I've been staring at the code for a long while, and I cannot see what
the problem is ...
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines. Boot with a
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