Provided by: varnish_7.5.0-3_amd64 
NAME
varnish-counters - Varnish counter field definitions
LCK – LOCK COUNTERS
Counters which track the activity in the different classes of mutex-locks.
The counts may be slightly wrong if there are more than one lock instantiated in each
class (ie: .creat > 1)
creat – counter - debug
Created locks
destroy – counter - debug
Destroyed locks
locks – counter - debug
Lock Operations
dbg_busy – counter - debug
Contended lock operations
If the lck debug bit is set: Lock operations which returned EBUSY on the first locking
attempt.
If the lck debug bit is unset, this counter will never be incremented even if lock
operations are contended.
dbg_try_fail – counter - debug
Contended trylock operations
If the lck debug bit is set: Trylock operations which returned EBUSY.
If the lck debug bit is unset, this counter will never be incremented even if lock
operations are contended.
MAIN – MAIN COUNTERS
summs – counter - debug
stat summ operations
Number of times per-thread statistics were summed into the global counters.
uptime – counter - info
Child process uptime
How long the child process has been running.
sess_conn – counter - info
Sessions accepted
Count of sessions successfully accepted
sess_fail – counter - info
Session accept failures
Count of failures to accept TCP connection.
This counter is the sum of the sess_fail_* counters, which give more detailed
information.
sess_fail_econnaborted – counter - info
Session accept failures: connection aborted
Detailed reason for sess_fail: Connection aborted by the client, usually harmless.
sess_fail_eintr – counter - info
Session accept failures: interrupted system call
Detailed reason for sess_fail: The accept() call was interrupted, usually harmless
sess_fail_emfile – counter - info
Session accept failures: too many open files
Detailed reason for sess_fail: No file descriptor was available. Consider raising
RLIMIT_NOFILE (see ulimit -n).
sess_fail_ebadf – counter - info
Session accept failures: bad file descriptor
Detailed reason for sess_fail: The listen socket file descriptor was invalid. Should
never happen.
sess_fail_enomem – counter - info
Session accept failures: not enough memory
Detailed reason for sess_fail: Most likely insufficient socket buffer memory. Should
never happen
sess_fail_other – counter - info
Session accept failures: other
Detailed reason for sess_fail: neither of the above, see SessError log (varnishlog -g
raw -i SessError).
client_req_400 – counter - info
Client requests received, subject to 400 errors
400 means we couldn't make sense of the request, it was malformed in some drastic way.
client_req_417 – counter - info
Client requests received, subject to 417 errors
417 means that something went wrong with an Expect: header.
client_req – counter - info
Good client requests received
The count of parseable client requests seen.
esi_req – counter - info
ESI subrequests
Number of ESI subrequests made.
cache_hit – counter - info
Cache hits
Count of cache hits. A cache hit indicates that an object has been delivered to a
client without fetching it from a backend server.
cache_hit_grace – counter - info
Cache grace hits
Count of cache hits with grace. A cache hit with grace is a cache hit where the object
is expired. Note that such hits are also included in the cache_hit counter.
cache_hitpass – counter - info
Cache hits for pass.
Count of hits for pass. A cache hit for pass indicates that Varnish is going to pass
the request to the backend and this decision has been cached in it self. This counts
how many times the cached decision is being used.
cache_hitmiss – counter - info
Cache hits for miss.
Count of hits for miss. A cache hit for miss indicates that Varnish is going to proceed
as for a cache miss without request coalescing, and this decision has been cached. This
counts how many times the cached decision is being used.
cache_miss – counter - info
Cache misses
Count of misses. A cache miss indicates the object was fetched from the backend before
delivering it to the client.
beresp_uncacheable – counter - info
Uncacheable backend responses
Count of backend responses considered uncacheable.
beresp_shortlived – counter - info
Shortlived objects
Count of objects created with ttl+grace+keep shorter than the 'shortlived' runtime
parameter.
backend_conn – counter - info
Backend conn. success
How many backend connections have successfully been established.
backend_unhealthy – counter - info
Backend conn. not attempted
backend_busy – counter - info
Backend conn. too many
backend_fail – counter - info
Backend conn. failures
backend_reuse – counter - info
Backend conn. reuses
Count of backend connection reuses. This counter is increased whenever we reuse a
recycled connection.
backend_recycle – counter - info
Backend conn. recycles
Count of backend connection recycles. This counter is increased whenever we have a
keep-alive connection that is put back into the pool of connections. It has not yet
been used, but it might be, unless the backend closes it.
backend_retry – counter - info
Backend conn. retry
fetch_head – counter - info
Fetch no body (HEAD)
beresp with no body because the request is HEAD.
fetch_length – counter - info
Fetch with Length
beresp.body with Content-Length.
fetch_chunked – counter - info
Fetch chunked
beresp.body with Chunked.
fetch_eof – counter - info
Fetch EOF
beresp.body with EOF.
fetch_bad – counter - info
Fetch bad T-E
beresp.body length/fetch could not be determined.
fetch_none – counter - info
Fetch no body
beresp.body empty
fetch_1xx – counter - info
Fetch no body (1xx)
beresp with no body because of 1XX response.
fetch_204 – counter - info
Fetch no body (204)
beresp with no body because of 204 response.
fetch_304 – counter - info
Fetch no body (304)
beresp with no body because of 304 response.
fetch_failed – counter - info
Fetch failed (all causes)
beresp fetch failed.
bgfetch_no_thread – counter - info
Background fetch failed (no thread)
A bgfetch triggered by a grace hit failed, no thread available.
pools – gauge - info
Number of thread pools
Number of thread pools. See also parameter thread_pools. NB: Presently pools cannot be
removed once created.
threads – gauge - info
Total number of threads
Number of threads in all pools. See also parameters thread_pools, thread_pool_min and
thread_pool_max.
threads_limited – counter - info
Threads hit max
Number of times more threads were needed, but limit was reached in a thread pool. See
also parameter thread_pool_max.
threads_created – counter - info
Threads created
Total number of threads created in all pools.
threads_destroyed – counter - info
Threads destroyed
Total number of threads destroyed in all pools.
threads_failed – counter - info
Thread creation failed
Number of times creating a thread failed. See VSL::Debug for diagnostics. See also
parameter thread_fail_delay.
thread_queue_len – gauge - info
Length of session queue
Length of session queue waiting for threads. NB: Only updates once per second. See also
parameter thread_queue_limit.
busy_sleep – counter - info
Number of requests sent to sleep on busy objhdr
Number of requests sent to sleep without a worker thread because they found a busy
object.
busy_wakeup – counter - info
Number of requests woken after sleep on busy objhdr
Number of requests taken off the busy object sleep list and rescheduled.
busy_killed – counter - info
Number of requests killed after sleep on busy objhdr
Number of requests killed from the busy object sleep list due to lack of resources.
sess_queued – counter - info
Sessions queued for thread
Number of times session was queued waiting for a thread. See also parameter
thread_queue_limit.
sess_dropped – counter - info
Sessions dropped for thread
Number of times an HTTP/1 session was dropped because the queue was too long already.
See also parameter thread_queue_limit.
req_dropped – counter - info
Requests dropped
Number of times an HTTP/2 stream was refused because the queue was too long already.
See also parameter thread_queue_limit.
req_reset – counter - info
Requests reset
Number of times a client left before the VCL processing of its requests completed. For
HTTP/2 sessions, either the stream was reset by an RST_STREAM frame from the client, or
a stream or connection error occurred.
n_object – gauge - info
object structs made
Approximate number of HTTP objects (headers + body, if present) in the cache.
n_vampireobject – gauge - diag
unresurrected objects
Number of unresurrected objects
n_objectcore – gauge - info
objectcore structs made
Approximate number of object metadata elements in the cache. Each object needs an
objectcore, extra objectcores are for hit-for-miss, hit-for-pass and busy objects.
n_objecthead – gauge - info
objecthead structs made
Approximate number of different hash entries in the cache.
n_backend – gauge - info
Number of backends
Number of backends known to us.
n_expired – counter - info
Number of expired objects
Number of objects that expired from cache because of old age.
n_superseded – counter - diag
Number of superseded objects
Number of times an object was superseded by a new one.
n_lru_nuked – counter - info
Number of LRU nuked objects
How many objects have been forcefully evicted from storage to make room for a new
object.
n_lru_moved – counter - diag
Number of LRU moved objects
Number of move operations done on the LRU list.
n_lru_limited – counter - info
Reached nuke_limit
Number of times more storage space were needed, but limit was reached in a nuke_limit.
See also parameter nuke_limit.
losthdr – counter - info
HTTP header overflows
s_sess – counter - info
Total sessions seen
n_pipe – gauge - info
Number of ongoing pipe sessions
pipe_limited – counter - info
Pipes hit pipe_sess_max
Number of times more pipes were needed, but the limit was reached. See also parameter
pipe_sess_max.
s_pipe – counter - info
Total pipe sessions seen
s_pass – counter - info
Total pass-ed requests seen
s_fetch – counter - info
Total backend fetches initiated
Total backend fetches initiated, including background fetches.
s_bgfetch – counter - info
Total backend background fetches initiated
s_synth – counter - info
Total synthetic responses made
s_req_hdrbytes – counter - info
Request header bytes
Total request header bytes received
s_req_bodybytes – counter - info
Request body bytes
Total request body bytes received
s_resp_hdrbytes – counter - info
Response header bytes
Total response header bytes transmitted
s_resp_bodybytes – counter - info
Response body bytes
Total response body bytes transmitted
s_pipe_hdrbytes – counter - info
Pipe request header bytes
Total request bytes received for piped sessions
s_pipe_in – counter - info
Piped bytes from client
Total number of bytes forwarded from clients in pipe sessions
s_pipe_out – counter - info
Piped bytes to client
Total number of bytes forwarded to clients in pipe sessions
sess_closed – counter - info
Session Closed
sess_closed_err – counter - info
Session Closed with error
Total number of sessions closed with errors. See sc_* diag counters for detailed
breakdown
sess_readahead – counter - info
Session Read Ahead
sess_herd – counter - diag
Session herd
Number of times the timeout_linger triggered
sc_rem_close – counter - diag
Session OK REM_CLOSE
Number of session closes with REM_CLOSE (Client Closed)
sc_req_close – counter - diag
Session OK REQ_CLOSE
Number of session closes with REQ_CLOSE (Client requested close)
sc_req_http10 – counter - diag
Session Err REQ_HTTP10
Number of session closes with Error REQ_HTTP10 (Proto < HTTP/1.1)
sc_rx_bad – counter - diag
Session Err RX_BAD
Number of session closes with Error RX_BAD (Received bad req/resp)
sc_rx_body – counter - diag
Session Err RX_BODY
Number of session closes with Error RX_BODY (Failure receiving req.body)
sc_rx_junk – counter - diag
Session Err RX_JUNK
Number of session closes with Error RX_JUNK (Received junk data)
sc_rx_overflow – counter - diag
Session Err RX_OVERFLOW
Number of session closes with Error RX_OVERFLOW (Received buffer overflow)
sc_rx_timeout – counter - diag
Session Err RX_TIMEOUT
Number of session closes with Error RX_TIMEOUT (Receive timeout)
sc_rx_close_idle – counter - diag
Session Err RX_CLOSE_IDLE
Number of session closes with Error RX_CLOSE_IDLE: timeout_idle has been exceeded while
waiting for a client request.
sc_tx_pipe – counter - diag
Session OK TX_PIPE
Number of session closes with TX_PIPE (Piped transaction)
sc_tx_error – counter - diag
Session Err TX_ERROR
Number of session closes with Error TX_ERROR (Error transaction)
sc_tx_eof – counter - diag
Session OK TX_EOF
Number of session closes with TX_EOF (EOF transmission)
sc_resp_close – counter - diag
Session OK RESP_CLOSE
Number of session closes with RESP_CLOSE (Backend/VCL requested close)
sc_overload – counter - diag
Session Err OVERLOAD
Number of session closes with Error OVERLOAD (Out of some resource)
sc_pipe_overflow – counter - diag
Session Err PIPE_OVERFLOW
Number of session closes with Error PIPE_OVERFLOW (Session pipe overflow)
sc_range_short – counter - diag
Session Err RANGE_SHORT
Number of session closes with Error RANGE_SHORT (Insufficient data for range)
sc_req_http20 – counter - diag
Session Err REQ_HTTP20
Number of session closes with Error REQ_HTTP20 (HTTP2 not accepted)
sc_vcl_failure – counter - diag
Session Err VCL_FAILURE
Number of session closes with Error VCL_FAILURE (VCL failure)
sc_rapid_reset – counter - diag
Session Err RAPID_RESET
Number of times we failed an http/2 session because it hit its configured limits for
the number of permitted rapid stream resets.
sc_bankrupt – counter - diag
Session Err BANKRUPT
Number of times we failed an http/2 session because all the streams were waiting for
their windows to be credited when h2_window_timeout triggered.
client_resp_500 – counter - diag
Delivery failed due to insufficient workspace.
Number of times we failed a response due to running out of workspace memory during
delivery.
ws_backend_overflow – counter - diag
workspace_backend overflows
Number of times we ran out of space in workspace_backend.
ws_client_overflow – counter - diag
workspace_client overflows
Number of times we ran out of space in workspace_client.
ws_thread_overflow – counter - diag
workspace_thread overflows
Number of times we ran out of space in workspace_thread.
ws_session_overflow – counter - diag
workspace_session overflows
Number of times we ran out of space in workspace_session.
shm_records – counter - diag
SHM records
Number of log records written to the shared memory log.
shm_writes – counter - diag
SHM writes
Number of individual writes to the shared memory log. A single write may batch multiple
records for bufferred tasks.
shm_flushes – counter - diag
SHM flushes due to overflow
Number of writes performed before the end of a bufferred task because adding a record
to a batch would exceed vsl_buffer.
shm_cont – counter - diag
SHM lock contention
Number of times a write had to wait for the lock.
shm_cycles – counter - diag
SHM cycles through VSL space
Number of times a write of log records would reach past the end of the shared memory
log, cycling back to the beginning.
shm_bytes – counter - diag
SHM bytes
Number of bytes written to the shared memory log.
backend_req – counter - info
Backend requests made
n_vcl – gauge - info
Number of loaded VCLs in total
n_vcl_avail – gauge - diag
Number of VCLs available
n_vcl_discard – gauge - diag
Number of discarded VCLs
vcl_fail – counter - info
VCL failures
Count of failures which prevented VCL from completing.
bans – gauge - info
Count of bans
Number of all bans in system, including bans superseded by newer bans and bans already
checked by the ban-lurker.
bans_completed – gauge - diag
Number of bans marked 'completed'
Number of bans which are no longer active, either because they got checked by the
ban-lurker or superseded by newer identical bans.
bans_obj – gauge - diag
Number of bans using obj.*
Number of bans which use obj.* variables. These bans can possibly be washed by the
ban-lurker.
bans_req – gauge - diag
Number of bans using req.*
Number of bans which use req.* variables. These bans can not be washed by the
ban-lurker.
bans_added – counter - diag
Bans added
Counter of bans added to ban list.
bans_deleted – counter - diag
Bans deleted
Counter of bans deleted from ban list.
bans_tested – counter - diag
Bans tested against objects (lookup)
Count of how many bans and objects have been tested against each other during hash
lookup.
bans_obj_killed – counter - diag
Objects killed by bans (lookup)
Number of objects killed by bans during object lookup.
bans_lurker_tested – counter - diag
Bans tested against objects (lurker)
Count of how many bans and objects have been tested against each other by the
ban-lurker.
bans_tests_tested – counter - diag
Ban tests tested against objects (lookup)
Count of how many tests and objects have been tested against each other during lookup.
'ban req.url == foo && req.http.host == bar' counts as one in 'bans_tested' and as two
in 'bans_tests_tested'
bans_lurker_tests_tested – counter - diag
Ban tests tested against objects (lurker)
Count of how many tests and objects have been tested against each other by the
ban-lurker. 'ban req.url == foo && req.http.host == bar' counts as one in 'bans_tested'
and as two in 'bans_tests_tested'
bans_lurker_obj_killed – counter - diag
Objects killed by bans (lurker)
Number of objects killed by the ban-lurker.
bans_lurker_obj_killed_cutoff – counter - diag
Objects killed by bans for cutoff (lurker)
Number of objects killed by the ban-lurker to keep the number of bans below ban_cutoff.
bans_dups – counter - diag
Bans superseded by other bans
Count of bans replaced by later identical bans.
bans_lurker_contention – counter - diag
Lurker gave way for lookup
Number of times the ban-lurker had to wait for lookups.
bans_persisted_bytes – gauge - diag
Bytes used by the persisted ban lists
Number of bytes used by the persisted ban lists.
bans_persisted_fragmentation – gauge - diag
Extra bytes in persisted ban lists due to fragmentation
Number of extra bytes accumulated through dropped and completed bans in the persistent
ban lists.
n_purges – counter - info
Number of purge operations executed
n_obj_purged – counter - info
Number of purged objects
exp_mailed – counter - diag
Number of objects mailed to expiry thread
Number of objects mailed to expiry thread for handling.
exp_received – counter - diag
Number of objects received by expiry thread
Number of objects received by expiry thread for handling.
hcb_nolock – counter - debug
HCB Lookups without lock
hcb_lock – counter - debug
HCB Lookups with lock
hcb_insert – counter - debug
HCB Inserts
esi_errors – counter - diag
ESI parse errors (unlock)
esi_warnings – counter - diag
ESI parse warnings (unlock)
vmods – gauge - info
Loaded VMODs
n_gzip – counter - info
Gzip operations
n_gunzip – counter - info
Gunzip operations
n_test_gunzip – counter - info
Test gunzip operations
Those operations occur when Varnish receives a compressed object from a backend. They
are done to verify the gzip stream while it's inserted in storage.
http1_iovs_flush – counter - info
Premature iovec flushes
Number of additional writes performed on HTTP1 connections because the number of IO
vectors was too small to submit all possible IO in one go. This number is configured
through the http1_iovs parameter for client connections and implicitly defined by the
amount of free workspace for backend connections.
MEMPOOL – MEMORY POOL COUNTERS
live – gauge - debug
In use
pool – gauge - debug
In Pool
sz_wanted – gauge - debug
Size requested
sz_actual – gauge - debug
Size allocated
allocs – counter - debug
Allocations
frees – counter - debug
Frees
recycle – counter - debug
Recycled from pool
timeout – counter - debug
Timed out from pool
toosmall – counter - debug
Too small to recycle
surplus – counter - debug
Too many for pool
randry – counter - debug
Pool ran dry
MGT – MANAGEMENT PROCESS COUNTERS
uptime – counter - info
Management process uptime
Uptime in seconds of the management process
child_start – counter - diag
Child process started
Number of times the child process has been started
child_exit – counter - diag
Child process normal exit
Number of times the child process has been cleanly stopped
child_stop – counter - diag
Child process unexpected exit
Number of times the child process has exited with an unexpected return code
child_died – counter - diag
Child process died (signal)
Number of times the child process has died due to signals
child_dump – counter - diag
Child process core dumped
Number of times the child process has produced core dumps
child_panic – counter - diag
Child process panic
Number of times the management process has caught a child panic
SMA – MALLOC STEVEDORE COUNTERS
c_req – counter - info
Allocator requests
Number of times the storage has been asked to provide a storage segment.
c_fail – counter - info
Allocator failures
Number of times the storage has failed to provide a storage segment.
c_bytes – counter - info
Bytes allocated
Number of total bytes allocated by this storage.
c_freed – counter - info
Bytes freed
Number of total bytes returned to this storage.
g_alloc – gauge - info
Allocations outstanding
Number of storage allocations outstanding.
g_bytes – gauge - info
Bytes outstanding
Number of bytes allocated from the storage.
g_space – gauge - info
Bytes available
Number of bytes left in the storage.
SMF – FILE STEVEDORE COUNTERS
c_req – counter - info
Allocator requests
Number of times the storage has been asked to provide a storage segment.
c_fail – counter - info
Allocator failures
Number of times the storage has failed to provide a storage segment.
c_bytes – counter - info
Bytes allocated
Number of total bytes allocated by this storage.
c_freed – counter - info
Bytes freed
Number of total bytes returned to this storage.
g_alloc – gauge - info
Allocations outstanding
Number of storage allocations outstanding.
g_bytes – gauge - info
Bytes outstanding
Number of bytes allocated from the storage.
g_space – gauge - info
Bytes available
Number of bytes left in the storage.
g_smf – gauge - info
N struct smf
g_smf_frag – gauge - info
N small free smf
g_smf_large – gauge - info
N large free smf
SMU – UMEM STEVEDORE COUNTERS
c_req – counter - info
Allocator requests
Number of times the storage has been asked to provide a storage segment.
c_fail – counter - info
Allocator failures
Number of times the storage has failed to provide a storage segment.
c_bytes – counter - info
Bytes allocated
Number of total bytes allocated by this storage.
c_freed – counter - info
Bytes freed
Number of total bytes returned to this storage.
g_alloc – gauge - info
Allocations outstanding
Number of storage allocations outstanding.
g_bytes – gauge - info
Bytes outstanding
Number of bytes allocated from the storage.
g_space – gauge - info
Bytes available
Number of bytes left in the storage.
VBE – BACKEND COUNTERS
happy – bitmap - info
Happy health probes
Represents the last probe results as a bitmap. Happy probes are bits set to 1, and the
unhappy ones are set to 0. The highest bits represent the oldest probes.
bereq_hdrbytes – counter - info
Request header bytes
Total backend request header bytes sent
bereq_bodybytes – counter - info
Request body bytes
Total backend request body bytes sent
beresp_hdrbytes – counter - info
Response header bytes
Total backend response header bytes received
beresp_bodybytes – counter - info
Response body bytes
Total backend response body bytes received
pipe_hdrbytes – counter - info
Pipe request header bytes
Total request bytes sent for piped sessions
pipe_out – counter - info
Piped bytes to backend
Total number of bytes forwarded to backend in pipe sessions
pipe_in – counter - info
Piped bytes from backend
Total number of bytes forwarded from backend in pipe sessions
conn – gauge - info
Concurrent connections used
The number of currently used connections to the backend. This number is always less or
equal to the number of connections to the backend (as, for example shown as ESTABLISHED
for TCP connections in netstat) due to connection pooling.
req – counter - info
Backend requests sent
unhealthy – counter - info
Fetches not attempted due to backend being unhealthy
busy – counter - info
Fetches not attempted due to backend being busy
Number of times the max_connections limit was reached
fail – counter - info
Connections failed
Counter of failed opens. Detailed reasons are given in the fail_* counters (DIAG level)
and in the log under the FetchError tag.
This counter is the sum of all detailed fail_* counters.
All fail_* counters may be slightly inaccurate for efficiency.
fail_eacces – counter - diag
Connections failed with EACCES or EPERM
fail_eaddrnotavail – counter - diag
Connections failed with EADDRNOTAVAIL
fail_econnrefused – counter - diag
Connections failed with ECONNREFUSED
fail_enetunreach – counter - diag
Connections failed with ENETUNREACH
fail_etimedout – counter - diag
Connections failed ETIMEDOUT
fail_other – counter - diag
Connections failed for other reason
helddown – counter - diag
Connection opens not attempted
Connections not attempted during the backend_local_error_holddown or
backend_remote_error_holddown interval after a fundamental connection issue.
AUTHORS
This man page was written by Lasse Karstensen, using content from vsc2rst written by
Tollef Fog Heen.
VARNISH-COUNTERS(7)