[Spread-users] high cpu load

[Dirk Vleugels]

Hi,

we're using mod_log_spread to combine the access logs of a 4-node LVS
cluster. The CPU usage of the spread daemons (on the apache
real-servers) seems quite high (up to 60%), while the loghost is
idle.

spmonitor shows the following numbers:

Status at cluster1 V 3.16. 0 (state 1, gstate 1) after 760918 seconds :
Membership  :  5  procs in 1 segments, leader is cluster1
rounds   : 617634183    tok_hurry : 2144198     memb change:       5
sent pack: 5706975      recv pack : 17722855    retrans    : 5540933
u retrans: 5386778      s retrans :  154155     b retrans  :       0
My_aru   : 14529311     Aru       : 14529311    Highest seq: 14529311
Sessions :     163      Groups    :       3     Window     :      60
Deliver M: 24034352     Deliver Pk: 24133000    Pers Window:      15
Delta Mes:  224840      Delta Pack:       0     Delta sec  :  129196
==================================

Monitor>
============================
Status at cluster3 V 3.16. 0 (state 1, gstate 1) after 761407 seconds :
Membership  :  5  procs in 1 segments, leader is cluster1
rounds   : 617636072    tok_hurry : 2087959     memb change:       9
sent pack: 5637323      recv pack : 23049662    retrans    : 5616992
u retrans: 5557058      s retrans :   59934     b retrans  :       0
My_aru   : 14529311     Aru       : 14529311    Highest seq: 14529311
Sessions :     128      Groups    :       3     Window     :      60
Deliver M: 24034364     Deliver Pk: 24133022    Pers Window:      15
Delta Mes:      12      Delta Pack:       0     Delta sec  :     489
==================================

Monitor>
============================
Status at cluster2 V 3.16. 0 (state 1, gstate 1) after 761172 seconds :
Membership  :  5  procs in 1 segments, leader is cluster1
rounds   : 617635235    tok_hurry : 2087845     memb change:       7
sent pack: 5329799      recv pack : 23207452    retrans    :  603931
u retrans:     416      s retrans :  603515     b retrans  :       0
My_aru   : 14529311     Aru       : 14529311    Highest seq: 14529311
Sessions :     148      Groups    :       3     Window     :      60
Deliver M: 24034359     Deliver Pk: 24133012    Pers Window:      15
Delta Mes:      -5      Delta Pack:       0     Delta sec  :    -235
==================================

Monitor>
============================
Status at cluster4 V 3.16. 0 (state 1, gstate 1) after 761531 seconds :
Membership  :  5  procs in 1 segments, leader is cluster1
rounds   : 617637065    tok_hurry : 2088017     memb change:      11
sent pack: 5715536      recv pack : 22496807    retrans    : 5397307
u retrans: 5163263      s retrans :  234044     b retrans  :       0
My_aru   : 14529311     Aru       : 14529311    Highest seq: 14529311
Sessions :     148      Groups    :       3     Window     :      60
Deliver M: 24034370     Deliver Pk: 24133048    Pers Window:      15
Delta Mes:      11      Delta Pack:       0     Delta sec  :     359

Monitor> 
============================
Status at loghost V 3.16. 0 (state 1, gstate 1) after 631721 seconds :
Membership  :  5  procs in 1 segments, leader is cluster1
rounds   : 595498478    tok_hurry : 1867064     memb change:       3
sent pack:       2      recv pack : 28541855    retrans    : 4951882
u retrans: 4809775      s retrans :  142107     b retrans  :       0
My_aru   : 14529246     Aru       : 14529246    Highest seq: 14529246
Sessions :       1      Groups    :       3     Window     :      60
Deliver M: 23809447     Deliver Pk: 23906883    Pers Window:      15
Delta Mes: -224800      Delta Pack:      58     Delta sec  : -129808
==================================


Any hints to reduce the cpu load? Something misconfigured? What
puzzles me are the membership changes. Afaik, only the first apache
instance does the logging, so the start of more httpd's shouldn't 
affect this counter.

Regards,
Dirk

-- 
Dirk Vleugels                           E-Mail: dvl at 2scale.net
2scale GmbH                             Phone:  +49 231 28 661 52
Am Rosenplätzchen 20                    Fax:    +49 231 28 661 59
44269 Dortmund, Germany                 Mobile: +49 173 28 106 61