Bug #1729

carp hash balancing not working properly

Added by frieder 169 days ago. Updated 105 days ago.

Status:New Start:
Priority:High Due date:
Assigned to:jan % Done:

0%
Category:mod_proxy_backend_http
Target version:1.5.0
Pending:

No

 Resolution:

Description

We're using mod_proxy_backend_http for balancing image requests to our squids with balance type carp.
One Backend gets ~ 10x more requests then the other..

My config:
server.modules += ( "mod_proxy_core", "mod_proxy_backend_http")

$HTTPurl =~ "^/xa/" {
proxy-core.balancer = "carp"
proxy-core.protocol = "http"
proxy-core.allow-x-sendfile = "enable"
proxy-core.backends = ( "192.168.66.201:82" )
proxy-core.max-pool-size = 256
}

$HTTPurl =~ "^/xb/s/" {
proxy-core.balancer = "carp"
proxy-core.protocol = "http"
proxy-core.allow-x-sendfile = "enable"
proxy-core.backends = ( "192.168.66.206:82", "192.168.66.205:82" )
proxy-core.max-pool-size = 1024
}

$HTTPurl =~ "^/xb/n/" {
...}

My problem is with the /xb/s balancing: i attach two munin graphics from our squids (both using excactly the same hardware and config) - one has about 200-300 req/s, the other 20-30.
/xa is hit hard with 1000-1500req/s and works fine - so my backends aren't the problem..

squid205_requests-week.png - first munin graph (29.1 KB) frieder, 07/22/2008 10:25 AM

squid206_requests-week.png - seond munin graph (30.8 KB) frieder, 07/22/2008 10:26 AM

History

07/22/2008 10:27 AM - frieder

/server-statistics:

proxy-core.0.backends."192.168.66.201:82".load: 0
proxy-core.0.backends."192.168.66.201:82".pool_size: 0
proxy-core.0.backends."192.168.66.201:82".requests: 96345
proxy-core.0.backends."192.168.66.201:82".requests_failed: 0
proxy-core.0.backlogged: 0
proxy-core.1.backends."192.168.66.205:82".load: 0
proxy-core.1.backends."192.168.66.205:82".pool_size: 0
proxy-core.1.backends."192.168.66.205:82".requests: 2507276
proxy-core.1.backends."192.168.66.205:82".requests_failed: 0
proxy-core.1.backends."192.168.66.206:82".load: 0
proxy-core.1.backends."192.168.66.206:82".pool_size: 7
proxy-core.1.backends."192.168.66.206:82".requests: 40270544
proxy-core.1.backends."192.168.66.206:82".requests_failed: 0
proxy-core.1.backlogged: 0
proxy-core.2.backends."192.168.66.202:82".load: 0
proxy-core.2.backends."192.168.66.202:82".pool_size: 2
proxy-core.2.backends."192.168.66.202:82".requests: 6538500
proxy-core.2.backends."192.168.66.202:82".requests_failed: 0
proxy-core.2.backends."192.168.66.203:82".load: 0
proxy-core.2.backends."192.168.66.203:82".pool_size: 3
proxy-core.2.backends."192.168.66.203:82".requests: 5842223
proxy-core.2.backends."192.168.66.203:82".requests_failed: 0
proxy-core.2.backlogged: 0
proxy-core.requests: 55254888

09/24/2008 09:32 PM - Anonymous

-- Chris Bolt <chrisbolt

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