assert(kern->metadata->conf->attr.overwrite
== DEFAULT_CHANNEL_OVERWRITE);
assert(kern->metadata->conf->attr.subbuf_size
assert(kern->metadata->conf->attr.overwrite
== DEFAULT_CHANNEL_OVERWRITE);
assert(kern->metadata->conf->attr.subbuf_size
assert(kern->metadata->conf->attr.num_subbuf
== DEFAULT_METADATA_SUBBUF_NUM);
assert(kern->metadata->conf->attr.switch_timer_interval
assert(kern->metadata->conf->attr.num_subbuf
== DEFAULT_METADATA_SUBBUF_NUM);
assert(kern->metadata->conf->attr.switch_timer_interval