Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Lars Ellenberg wrote: > please reply to the list. > > / 2004-04-26 12:17:52 +0200 > \ Andreas Semt: > >>>>I use DRBD 0.6.12 (with heartbeat 1.21). Sometimes I get some real high >>>>load on my machine (load average around 6) and a zombie process like >>>>drbd_syncer_2 or drbd_syncer_3. I believe the zombie process causes the >>>>high load. Also i lost a drbd connection without reason (one connection >>>>of four). >>>>Additional information: the zombie processes disappear after some time >>>>and the load is normal again. Zombies exist only on the drbd "PRIMARY" >>>>machine (all drbd devices in primary mode). >>>> >>>>My questions: >>>> >>>>1. Could it be a zombie process who killed the drbd connection? >>> >>> >>>No. It is only killed *after* the connection was lost. >>>Unfortunately it is not always reaped immediately. >>>Zombie processes cannot cause load, because they are dead. >>>They only waste some memory and process slots. >>> >> >>Okay, the high load is explained in the FAQ (sorry). >>Can you say what exactly drbd_syncer and drbd_asender doing? > > > > syncer reads in the blocks that need to be synced from local disk, > and sends over to the peer. > > asender sends ACKknowledgement packets for written data, and for > drbd-pings, and itself sends drbd-ping-requests if neccessary. > > >>>>2. Why these Zombies live on my machine? >>> >>>If you care, you can use 0.6.12 CVS HEAD, which differs basically only >>>by a "reparent to init" call right after our thread startup, as it >>>should have been from the very begining. now, the "zombies" are reaped >>>by init almost immediately after their death. >>> >> >>Is that a common behavior of drbd (to create "zombies") or a bug or >>something else? > > > Not a bug, as long as they get reaped eventually. > Unusual bahaviour, if it takes "long" to reap them. > A bug if they stay around for ever. > > Unusual in general, because typically kernel threads should be > reparented to init anyways. > "historically" drbd wanted to reap its child threads itself. > With every mail i learn a lot! Thanks! -- Best regards, Andreas Semt