mdadm raid5

[lord_Niedzwiedz]

	Mam problem z macierzami RAID5 mdadm.

[root w Misiek ~]# hdparm -tT /dev/md2
/dev/md2:
  Timing cached reads:   7378 MB in  2.00 seconds = 3689.51 MB/sec
  Timing buffered disk reads: 666 MB in  3.00 seconds = 221.96 MB/sec
[root w louve.komandor.net ~]# hdparm -tT /dev/md4
/dev/md4:
  Timing cached reads:   4572 MB in  2.00 seconds = 2286.55 MB/sec
  Timing buffered disk reads:  20 MB in  3.36 seconds =   5.95 MB/sec

[root w Misiek ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid1]
md4 : active raid5 sdb4[1] sdc4[4] sdd4[2]
       2783457792 blocks super 1.2 level 5, 512k chunk, algorithm 2 
[4/3] [_UUU]

md1 : active raid1 sda1[0] sdc1[3] sdb1[1]
       489856 blocks [4/3] [UU_U]

md2 : active raid5 sda2[6] sdc2[4] sdb2[5]
146485248 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/3] [UU_U]


Jeśli dam teraz:
[root w Misiek ~]# mdadm --manage /dev/md4 --add /dev/sda4
mdadm: re-added /dev/sda4
[root w Misiek ~]# cat /proc/mdstat 

Personalities : [raid6] [raid5] [raid4] [raid1]
md4 : active raid5 sda4[5] sdb4[1] sdc4[4] sdd4[2]
       2783457792 blocks super 1.2 level 5, 512k chunk, algorithm 2 
[4/3] [_UUU]
       [>....................]  recovery =  0.0% (12/927819264) 
finish=2899435.1min speed=4K/sec

md1 : active raid1 sda1[0] sdc1[3] sdb1[1]
       489856 blocks [4/3] [UU_U]

md2 : active raid5 sda2[6] sdc2[4] sdb2[5]
146485248 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/3] [UU_U]


Jak wi8dać MD4 chce się odbudowywać koszmarnie wolno !! ;-(((
Co z tym zrobić, jak to naprawić ??!!??!!

Dziwna sprawa. Jak korzystam z RAID'a md2 to wszystko śmiga na 3 dyskach 
(czwarty specjalnie wypiety - spowalniało).

Natomiast jak koszystam z md4 to jest total zwiecha i kicha.
Co to może być ??