Varnish Monitoring Extension

This extension works only with the standalone machine agent.

Use Case

Varnish Cache is a web application accelerator also known as a caching HTTP reverse proxy. You install it in front of any server that speaks HTTP and configure it to cache the contents. The varnish-monitoring-extension gathers cache metrics exposed through Varnish's REST API and sends them to the AppDynamics Metric Browser.

Installation

1. Type 'ant package' in the command line from the varnish-monitoring-extension directory.
2. Deploy the file VarnishMonitor.zip found in the 'dist' directory into the <machineagent install dir>/monitors/ directory.
3. Unzip the deployed file.
4. Open <machineagent install dir>/monitors/VarnishMonitor/monitor.xml and configure the Varnish parameters.

   	 <argument name="host" is-required="true" default-value="localhost"/>
        <argument name="port" is-required="true" default-value="6085"/>
        <argument name="username" is-required="true" default-value="username"/>
        <argument name="password" is-required="true" default-value="password"/>
        <argument name="enabled-metrics-path" is-required="true" default-value="monitors/VarnishMonitor/conf/EnabledMetrics.xml"/>
   

5. Open <machineagent install dir>/monitors/VarnishMonitor/conf/EnabledMetrics.xml and configure the list of enabled metrics. Here is a sample configuration of the enabled metrics:

   	 <Metric name="mem_free"/>
   	 <Metric name="mem_total"/>
   

6. Restart the machine agent.
7. In the AppDynamics Metric Browser, look for: Application Infrastructure Performance | <Tier> | Custom Metrics | Varnish

Directory Structure

Directory/File	Description
conf	Contains the monitor.xml, EnabledMetrics.xml
lib	Contains third-party project references
src	Contains source code of the Varnish monitoring extension
dist	Only obtained when using ant. Run 'ant build' to get binaries. Run 'ant package' to get the distributable .zip file
build.xml	Ant build script to package the project (required only if changing Java code)

Metrics

NOTE: By default, only metrics from "client_conn" to "dir_dns_cache_full" in the following list are reported. This can be changed in the EnabledMetrics.xml file.

Metric Name	Description
client_conn	Client connections accepted
client_drop	Connection dropped, no sess/wrk
client_req	Client requests received
cache_hit	Cache hits
cache_hitpass	Cache hits for pass
cache_miss	Cache misses
backend_conn	Backend conn. success
backend_unhealthy	Backend conn. not attempted
backend_busy	Backend conn. too many
backend_fail	Backend conn. failures
backend_reuse	Backend conn. reuses
backend_toolate	Backend conn. was closed
backend_recycle	Backend conn. recycles
backend_retry	Backend conn. retry
n_wrk	N worker threads
n_wrk_create	N worker threads created
n_wrk_failed	N worker threads not created
n_wrk_max	N worker threads limited
n_wrk_lqueue	work request queue length
n_wrk_queued	N queued work requests
n_wrk_drop	N dropped work requests
n_backend	N backends
n_expired	N expired objects
s_sess	Total Sessions
s_req	Total Requests
uptime	Client uptime
dir_dns_lookups	DNS director lookups
dir_dns_failed	DNS director failed lookups
dir_dns_hit	DNS director cached lookups hit
dir_dns_cache_full	DNS director full dnscache
timestamp	Timestamp in milliseconds
fetch_head	Fetch head
fetch_length	Fetch with Length
fetch_chunked	Fetch chunked
fetch_eof	Fetch EOF
fetch_bad	Fetch had bad headers
fetch_close	Fetch wanted close
fetch_oldhttp	Fetch pre HTTP/1.1 closed
fetch_zero	Fetch zero len
fetch_failed	Fetch failed
fetch_1xx	Fetch no body (1xx)
fetch_204	Fetch no body (204)
fetch_304	Fetch no body (304)
n_sess_mem	N struct sess_mem
n_sess	N struct sess
n_object	N struct object
n_vampireobject	N unresurrected objects
n_objectcore	N struct objectcore
n_objecthead	N struct objecthead
n_waitinglist	N struct waitinglist
n_vbc	N struct vbc
n_lru_nuked	N LRU nuked objects
n_lru_moved	N LRU moved objects
losthdr	HTTP header overflows
n_objsendfile	Objects sent with sendfile
n_objwrite	Objects sent with write
n_objoverflow	Objects overflowing workspace
s_pipe	Total pipe
s_pass	Total pass
s_fetch	Total fetch
s_hdrbytes	Total header bytes
s_bodybytes	Total body bytes
sess_closed	Session Closed
sess_pipeline	Session Pipeline
sess_readahead	Session Read Ahead
sess_linger	Session Linger
sess_herd	Session herd
shm_records	SHM records
shm_writes	SHM writes
shm_flushes	SHM flushes due to overflow
shm_cont	SHM MTX contention
shm_cycles	SHM cycles through buffer
sms_nreq	SMS allocator requests
sms_nobj	SMS outstanding allocations
sms_nbytes	SMS outstanding bytes
sms_balloc	SMS bytes allocated
sms_bfree	SMS bytes freed
backend_req	Backend requests made
n_vcl	N vcl total
n_vcl_avail	N vcl available
n_vcl_discard	N vcl discarded
n_ban	N total active bans
n_ban_gone	N total gone bans
n_ban_add	N new bans added
n_ban_retire	N old bans deleted
n_ban_obj_test	N objects tested
n_ban_re_test	N regexps tested against
n_ban_dups	N duplicate bans removed
hcb_nolock	HCB Lookups without lock
hcb_lock	HCB Lookups with lock
hcb_insert	HCB Inserts
esi_errors	ESI parse errors (unlock)
esi_warnings	ESI parse warnings (unlock)
accept_fail	Accept failures
client_drop_late	Connection dropped late
vmods	Loaded VMODs
n_gzip	Gzip operations
n_gunzip	Gunzip operations
sess_pipe_overflow	Dropped sessions due to session pipe overflow
LCK.sms.creat	Created locks
LCK.sms.destroy	Destroyed locks
LCK.sms.locks	Lock Operations
LCK.sms.colls	Collisions
LCK.smp.creat	Created locks
LCK.smp.destroy	Destroyed locks
LCK.smp.locks	Lock Operations
LCK.smp.colls	Collisions
LCK.sma.creat	Created locks
LCK.sma.destroy	Destroyed locks
LCK.sma.locks	Lock Operations
LCK.sma.colls	Collisions
LCK.smf.creat	Created locks
LCK.smf.destroy	Destroyed locks
LCK.smf.locks	Lock Operations
LCK.smf.colls	Collisions
LCK.hsl.creat	Created locks
LCK.hsl.destroy	Destroyed locks
LCK.hsl.locks	Lock Operations
LCK.hsl.colls	Collisions
LCK.hcb.creat	Created locks
LCK.hcb.destroy	Destroyed locks
LCK.hcb.locks	Lock Operations
LCK.hcb.colls	Collisions
LCK.hcl.creat	Created locks
LCK.hcl.destroy	Destroyed locks
LCK.hcl.locks	Lock Operations
LCK.hcl.colls	Collisions
LCK.vcl.creat	Created locks
LCK.vcl.destroy	Destroyed locks
LCK.vcl.locks	Lock Operations
LCK.vcl.colls	Collisions
LCK.stat.creat	Created locks
LCK.stat.destroy	Destroyed locks
LCK.stat.locks	Lock Operations
LCK.stat.colls	Collisions
LCK.sessmem.creat	Created locks
LCK.sessmem.destroy	Destroyed locks
LCK.sessmem.locks	Lock Operations
LCK.sessmem.colls	Collisions
LCK.wstat.creat	Created locks
LCK.wstat.destroy	Destroyed locks
LCK.wstat.locks	Lock Operations
LCK.wstat.colls	Collisions
LCK.herder.creat	Created locks
LCK.herder.destroy	Destroyed locks
LCK.herder.locks	Lock Operations
LCK.herder.colls	Collisions
LCK.wq.creat	Created locks
LCK.wq.destroy	Destroyed locks
LCK.wq.locks	Lock Operations
LCK.wq.colls	Collisions
LCK.objhdr.creat	Created locks
LCK.objhdr.destroy	Destroyed locks
LCK.objhdr.locks	Lock Operations
LCK.objhdr.colls	Collisions
LCK.exp.creat	Created locks
LCK.exp.destroy	Destroyed locks
LCK.exp.locks	Lock Operations
LCK.exp.colls	Collisions
LCK.lru.creat	Created locks
LCK.lru.destroy	Destroyed locks
LCK.lru.locks	Lock Operations
LCK.lru.colls	Collisions
LCK.cli.creat	Created locks
LCK.cli.destroy	Destroyed locks
LCK.cli.locks	Lock Operations
LCK.cli.colls	Collisions
LCK.ban.creat	Created locks
LCK.ban.destroy	Destroyed locks
LCK.ban.locks	Lock Operations
LCK.ban.colls	Collisions
LCK.vbp.creat	Created locks
LCK.vbp.destroy	Destroyed locks
LCK.vbp.locks	Lock Operations
LCK.vbp.colls	Collisions
LCK.vbe.creat	Created locks
LCK.vbe.destroy	Destroyed locks
LCK.vbe.locks	Lock Operations
LCK.vbe.colls	Collisions
LCK.backend.creat	Created locks
LCK.backend.destroy	Destroyed locks
LCK.backend.locks	Lock Operations
LCK.backend.colls	Collisions
SMA.s0.c_req	Allocator requests
SMA.s0.c_fail	Allocator failures
SMA.s0.c_bytes	Bytes allocated
SMA.s0.c_freed	Bytes freed
SMA.s0.g_alloc	Allocations outstanding
SMA.s0.g_bytes	Bytes outstanding
SMA.s0.g_space	Bytes available
SMA.Transient.c_req	Allocator requests
SMA.Transient.c_fail	Allocator failures
SMA.Transient.c_bytes	Bytes allocated
SMA.Transient.c_freed	Bytes freed
SMA.Transient.g_alloc	Allocations outstanding
SMA.Transient.g_bytes	Bytes outstanding
SMA.Transient.g_space	Bytes available
VBE.default.vcls	VCL references
VBE.default.happy	Happy health probes

Custom Dashboard

##Contributing

Always feel free to fork and contribute any changes directly here on GitHub.

##Community

Find out more in the AppSphere community.

##Support

For any questions or feature request, please contact AppDynamics Center of Excellence.