appstream refresh stuck at 100% CPU on xenial

[Timo Jyrinki]

After a few hours of working today I started wondering what was consuming my battery:

 %CPU %MEM TIME+ COMMAND
100,0 0,5 167:06.10 appstreamcli

"appstreamcli refresh" is running according to ps. I need to kill it in order to continue sanely so I may not be getting all the necessary debugging out of it, but here's something.

sudo gdb -p to the process, continue, break and backtrace:
0x00007f14285f9b23 in yaml_parser_parse () from /usr/lib/x86_64-linux-gnu/libyaml-0.so.2
(gdb) bt
#0 0x00007f14285f9b23 in yaml_parser_parse () from /usr/lib/x86_64-linux-gnu/libyaml-0.so.2
#1 0x00007f1429ea9c4c in as_yamldata_parse_distro_data () from /usr/lib/x86_64-linux-gnu/libappstream.so.3
#2 0x00007f1429eab537 in as_metadata_parse_yaml () from /usr/lib/x86_64-linux-gnu/libappstream.so.3
#3 0x00007f1429eabc55 in as_metadata_parse_file () from /usr/lib/x86_64-linux-gnu/libappstream.so.3
#4 0x00007f1429eaed49 in as_data_pool_update () from /usr/lib/x86_64-linux-gnu/libappstream.so.3
#5 0x00007f1429ea4272 in as_cache_builder_refresh () from /usr/lib/x86_64-linux-gnu/libappstream.so.3
#6 0x00000000004049de in ascli_refresh_cache ()
#7 0x0000000000403ceb in as_client_run ()
#8 0x00007f1429ad2830 in __libc_start_main (main=0x403490 <main>, argc=2, argv=0x7fff509d0768, init=<optimized out>,
    fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff509d0758) at ../csu/libc-start.c:291
#9 0x0000000000403519 in _start ()

And seems to fluctuate between eg yaml_event_delete, yaml_parser_parse, but it seems to be stuck in that as_yamldata_parse_distro_data.

Strace does not seem to output anything when attaching, or I'm doing something wrong:
$ sudo strace -p 14708
strace: Process 14708 attached
strace: [ Process PID=14708 runs in x32 mode. ]
^Cstrace: Process 14708 detached

I have a snapshot of /var/cache/app-info in store if needed. Nothing under xapian/ has timestamp newer than 3h ago when the process had started, and xmls/fwupd.xml is over an hour old too.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Leopoldo Pena (leopenausa)]

I can confirm the same issue on my laptop with Xenial.

[Timo Jyrinki (timo-jyrinki)]

Hah, sounds like fix would be released 3h ago and that's why I didn't see any bug filed :D

Bug #1579712