VARNISHD()VARNISHD()NAMEvarnishd - HTTP accelerator daemon
SYNOPSISvarnishd [-a address[:port]] [-b host[:port]] [-C] [-d] [-f config]
[-F] [-g group] [-h type[,options]] [-i identity] [-l
shl[,free[,fill]]] [-M address:port] [-n name] [-P file] [-p
param=value] [-r param[,param...] [-s [name=]kind[,options]]
[-S secret-file] [-T address[:port]] [-t ttl] [-u user] [-V]
DESCRIPTION
The varnishd daemon accepts HTTP requests from clients, passes them on
to a backend server and caches the returned documents to better satisfy
future requests for the same document.
OPTIONS-a address[:port][,address[:port][...]
Listen for client requests on the specified address and port.
The address can be a host name (“localhost”), an IPv4 dot‐
ted-quad (“127.0.0.1”), or an IPv6 address enclosed in square
brackets (“[::1]”). If address is not specified, varnishd will
listen on all available IPv4 and IPv6 interfaces. If port is
not specified, the default HTTP port as listed in /etc/services
is used. Multiple listening addresses and ports can be speci‐
fied as a whitespace or comma -separated list.
-b host[:port]
Use the specified host as backend server. If port is not speci‐
fied, the default is 8080.
-C Print VCL code compiled to C language and exit. Specify the VCL
file to compile with the -f option.
-d Enables debugging mode: The parent process runs in the fore‐
ground with a CLI connection on stdin/stdout, and the child
process must be started explicitly with a CLI command. Termi‐
nating the parent process will also terminate the child.
-f config
Use the specified VCL configuration file instead of the builtin
default. See vcl(7) for details on VCL syntax. When no configu‐
ration is supplied varnishd will not start the cache process.
-F Run in the foreground.
-g group
Specifies the name of an unprivileged group to which the child
process should switch before it starts accepting connections.
This is a shortcut for specifying the group run-time parameter.
-h type[,options]
Specifies the hash algorithm. See Hash Algorithms for a list of
supported algorithms.
-i identity
Specify the identity of the Varnish server. This can be
accessed using server.identity from VCL
-l shl[,free[,fill]]
Specifies size of shmlog file. shl is the store for the shared
memory log records [80m], free is the store for other alloca‐
tions [1m] and fill determines how the log is [+]. Scaling suf‐
fixes like 'k', 'm' can be used up to (e)tabytes. Default is 80
Megabytes.
-M address:port
Connect to this port and offer the command line interface.
Think of it as a reverse shell. When running with -M and there
is no backend defined the child process (the cache) will not
start initially.
-n name
Specify the name for this instance. Amonst other things, this
name is used to construct the name of the directory in which
varnishd keeps temporary files and persistent state. If the
specified name begins with a forward slash, it is interpreted as
the absolute path to the directory which should be used for this
purpose.
-P file
Write the process's PID to the specified file.
-p param=value
Set the parameter specified by param to the specified value.
See Run-Time Parameters for a list of parameters. This option
can be used multiple times to specify multiple parameters.
-r param[,param...]
Make the listed parameters read only. This gives the system
administrator a way to limit what the Varnish CLI can do. Con‐
sider making parameters such as user, group, cc_command,
vcc_allow_inline_c read only as these can potentially be used to
escalate privileges from the CLI. Protecting listen_address may
also be a good idea.
-s [name=]type[,options]
Use the specified storage backend. The storage backends can be
one of the following:
· malloc[,size]
· file[,path[,size[,granularity]]]
· persistent,path,size
See Storage Types in the Users Guide for more information on the
various storage backends. This option can be used multiple
times to specify multiple storage files. Names are referenced in
logs, vcl, statistics, etc.
-S file
Path to a file containing a secret used for authorizing access
to the management port.
-T address[:port]
Offer a management interface on the specified address and port.
See Management Interface for a list of management commands.
-t ttl Specifies a hard minimum time to live for cached documents. This
is a shortcut for specifying the default_ttl run-time parameter.
-u user
Specifies the name of an unprivileged user to which the child
process should switch before it starts accepting connections.
This is a shortcut for specifying the user runtime parameter.
If specifying both a user and a group, the user should be speci‐
fied first.
-V Display the version number and exit.
Hash Algorithms
The following hash algorithms are available:
critbit
A self-scaling tree structure. The default hash algorithm in
Varnish Cache 2.1 and onwards. In comparison to a more
traditional B tree the critbit tree is almost completely
lockless. Do not change this unless you are certain what
you're doing.
simple_list
A simple doubly-linked list. Not recommended for production
use.
classic[,buckets]
A standard hash table. The hash key is the CRC32 of the object's
URL modulo the size of the hash table. Each table entry points
to a list of elements which share the same hash key. The buckets
parameter specifies the number of entries in the hash table.
The default is 16383.
Storage Types
The following storage types are available:
malloc
syntax: malloc[,size]
malloc is a memory based backend.
file
syntax: file[,path[,size[,granularity]]]
The file backend stores data in a file on disk. The file will be
accessed using mmap.
persistent (experimental)
syntax: persistent,path,size
Persistent storage. Varnish will store objects in a file in a manner
that will secure the survival of most of the objects in the event of a
planned or unplanned shutdown of Varnish. The persistent storage back‐
end has multiple issues with it and will likely be removed from a
future version of Varnish.
Management Interface
If the -T option was specified, varnishd will offer a command-line man‐
agement interface on the specified address and port. The recommended
way of connecting to the command-line management interface is through
varnishadm(1).
The commands available are documented in varnish(7).
Run-Time Parameters
Runtime parameters are marked with shorthand flags to avoid repeating
the same text over and over in the table below. The meaning of the
flags are:
experimental
We have no solid information about good/bad/optimal values for
this parameter. Feedback with experience and observations are
most welcome.
delayed
This parameter can be changed on the fly, but will not take
effect immediately.
restart
The worker process must be stopped and restarted, before this
parameter takes effect.
reload The VCL programs must be reloaded for this parameter to take
effect.
Here is a list of all parameters, current as of last time we remembered
to update the manual page. This text is produced from the same text
you will find in the CLI if you use the param.show command, so should
there be a new parameter which is not listed here, you can find the
description using the CLI commands.
Be aware that on 32 bit systems, certain default values, such as
workspace_client (=16k), thread_pool_workspace (=16k), http_resp_size
(=8k), http_req_size (=12k), gzip_stack_buffer (=4k) and
thread_pool_stack (=64k) are reduced relative to the values listed
here, in order to conserve VM space.
acceptor_sleep_decay
· Default: 0.9
· Minimum: 0
· Maximum: 1
· Flags: experimental
If we run out of resources, such as file descriptors or worker threads,
the acceptor will sleep between accepts. This parameter (multiplica‐
tively) reduce the sleep duration for each succesfull accept. (ie: 0.9
= reduce by 10%)
acceptor_sleep_incr
· Units: s
· Default: 0.001
· Minimum: 0.000
· Maximum: 1.000
· Flags: experimental
If we run out of resources, such as file descriptors or worker threads,
the acceptor will sleep between accepts. This parameter control how
much longer we sleep, each time we fail to accept a new connection.
acceptor_sleep_max
· Units: s
· Default: 0.050
· Minimum: 0.000
· Maximum: 10.000
· Flags: experimental
If we run out of resources, such as file descriptors or worker threads,
the acceptor will sleep between accepts. This parameter limits how
long it can sleep between attempts to accept new connections.
auto_restart
· Units: bool
· Default: on
Restart child process automatically if it dies.
ban_dups
· Units: bool
· Default: on
Elimited older identical bans when new bans are created. This test is
CPU intensive and scales with the number and complexity of active
(non-Gone) bans. If identical bans are frequent, the amount of CPU
needed to actually test the bans will be similarly reduced.
ban_lurker_age
· Units: s
· Default: 60.000
· Minimum: 0.000
The ban lurker does not process bans until they are this old. Right
when a ban is added, the most frequently hit objects will get tested
against it as part of object lookup. This parameter prevents the
ban-lurker from kicking in, until the rush is over.
ban_lurker_batch
· Default: 1000
· Minimum: 1
How many objects the ban lurker examines before taking a
ban_lurker_sleep. Use this to pace the ban lurker so it does not eat
too much CPU.
ban_lurker_sleep
· Units: s
· Default: 0.010
· Minimum: 0.000
The ban lurker thread sleeps between work batches, in order to not
monopolize CPU power. When nothing is done, it sleeps a fraction of a
second before looking for new work to do. A value of zero disables the
ban lurker.
between_bytes_timeout
· Units: s
· Default: 60.000
· Minimum: 0.000
Default timeout between bytes when receiving data from backend. We only
wait for this many seconds between bytes before giving up. A value of 0
means it will never time out. VCL can override this default value for
each backend request and backend request. This parameter does not apply
to pipe.
busyobj_worker_cache
· Units: bool
· Default: off
Cache free busyobj per worker thread. Disable this if you have very
high hitrates and want to save the memory of one busyobj per worker
thread.
cc_command
· Default: "exec gcc -std=gnu99 -Os-fomit-frame-pointer
-D_GNU_SOURCE-Wall-Werror -Wno-error=unused-result -fpic
-shared -Wl,-x -o %o %s"
· Flags: must_reload
Command used for compiling the C source code to a dlopen(3) loadable
object. Any occurrence of %s in the string will be replaced with the
source file name, and %o will be replaced with the output file name.
cli_buffer
· Units: bytes
· Default: 8k
· Minimum: 4k
Size of buffer for CLI command input. You may need to increase this if
you have big VCL files and use the vcl.inline CLI command. NB: Must be
specified with -p to have effect.
cli_limit
· Units: bytes
· Default: 48k
· Minimum: 128b
· Maximum: 99999999b
Maximum size of CLI response. If the response exceeds this limit, the
reponse code will be 201 instead of 200 and the last line will indicate
the truncation.
cli_timeout
· Units: seconds
· Default: 60.000
· Minimum: 0.000
Timeout for the childs replies to CLI requests from the mgt_param.
clock_skew
· Units: s
· Default: 10
· Minimum: 0
How much clockskew we are willing to accept between the backend and our
own clock.
connect_timeout
· Units: s
· Default: 3.500
· Minimum: 0.000
Default connection timeout for backend connections. We only try to con‐
nect to the backend for this many seconds before giving up. VCL can
override this default value for each backend and backend request.
critbit_cooloff
· Units: s
· Default: 180.000
· Minimum: 60.000
· Maximum: 254.000
· Flags: wizard
How long time the critbit hasher keeps deleted objheads on the cooloff
list.
debug
· Default: none
Enable/Disable various kinds of debugging.
none Disable all debugging
Use +/- prefix to set/reset individual bits:
req_state
VSL Request state engine
workspace
VSL Workspace operations
waiter VSL Waiter internals
waitinglist
VSL Waitinglist events
syncvsl
Make VSL synchronous
hashedge
Edge cases in Hash
vclrel Rapid VCL release
lurker VSL Ban lurker
esi_chop
Chop ESI fetch to bits
default_grace
· Units: seconds
· Default: 10.000
· Minimum: 0.000
· Flags:
Default grace period. We will deliver an object this long after it has
expired, provided another thread is attempting to get a new copy.
default_keep
· Units: seconds
· Default: 0.000
· Minimum: 0.000
· Flags:
Default keep period. We will keep a useless object around this long,
making it available for conditional backend fetches. That means that
the object will be removed from the cache at the end of ttl+grace+keep.
default_ttl
· Units: seconds
· Default: 120.000
· Minimum: 0.000
· Flags:
The TTL assigned to objects if neither the backend nor the VCL code
assigns one.
feature
· Default: none
Enable/Disable various minor features.
none Disable all features.
Use +/- prefix to enable/disable individual feature:
short_panic
Short panic message.
wait_silo
Wait for persistent silo.
no_coredump
No coredumps.
esi_ignore_https
Treat HTTPS as HTTP in ESI:includes
esi_disable_xml_check
Don't check of body looks like XML
esi_ignore_other_elements
Ignore non-esi XML-elements
esi_remove_bom
Remove UTF-8 BOM
fetch_chunksize
· Units: bytes
· Default: 128k
· Minimum: 4k
· Flags: experimental
The default chunksize used by fetcher. This should be bigger than the
majority of objects with short TTLs. Internal limits in the stor‐
age_file module makes increases above 128kb a dubious idea.
fetch_maxchunksize
· Units: bytes
· Default: 0.25G
· Minimum: 64k
· Flags: experimental
The maximum chunksize we attempt to allocate from storage. Making this
too large may cause delays and storage fragmentation.
first_byte_timeout
· Units: s
· Default: 60.000
· Minimum: 0.000
Default timeout for receiving first byte from backend. We only wait for
this many seconds for the first byte before giving up. A value of 0
means it will never time out. VCL can override this default value for
each backend and backend request. This parameter does not apply to
pipe.
group
· Default: nogroup (65533)
· Flags: must_restart
The unprivileged group to run as.
gzip_buffer
· Units: bytes
· Default: 4k
· Minimum: 2k
· Flags: experimental
Size of malloc buffer used for gzip processing. These buffers are used
for in-transit data, for instance gunzip'ed data being sent to a
client.Making this space to small results in more overhead, writes to
sockets etc, making it too big is probably just a waste of memory.
gzip_level
· Default: 6
· Minimum: 0
· Maximum: 9
Gzip compression level: 0=debug, 1=fast, 9=best
gzip_memlevel
· Default: 8
· Minimum: 1
· Maximum: 9
Gzip memory level 1=slow/least, 9=fast/most compression. Memory impact
is 1=1k, 2=2k, ... 9=256k.
http_gzip_support
· Units: bool
· Default: on
Enable gzip support. When enabled Varnish request compressed objects
from the backend and store them compressed. If a client does not sup‐
port gzip encoding Varnish will uncompress compressed objects on
demand. Varnish will also rewrite the Accept-Encoding header of clients
indicating support for gzip to:
Accept-Encoding: gzip
Clients that do not support gzip will have their Accept-Encoding header
removed. For more information on how gzip is implemented please see the
chapter on gzip in the Varnish reference.
http_max_hdr
· Units: header lines
· Default: 64
· Minimum: 32
· Maximum: 65535
Maximum number of HTTP header lines we allow in
{req|resp|bereq|beresp}.http (obj.http is autosized to the exact number
of headers). Cheap, ~20 bytes, in terms of workspace memory. Note
that the first line occupies five header lines.
http_range_support
· Units: bool
· Default: on
Enable support for HTTP Range headers.
http_req_hdr_len
· Units: bytes
· Default: 8k
· Minimum: 40b
Maximum length of any HTTP client request header we will allow. The
limit is inclusive its continuation lines.
http_req_size
· Units: bytes
· Default: 12k
· Minimum: 0.25k
Maximum number of bytes of HTTP client request we will deal with. This
is a limit on all bytes up to the double blank line which ends the HTTP
request. The memory for the request is allocated from the client
workspace (param: workspace_client) and this parameter limits how much
of that the request is allowed to take up.
http_resp_hdr_len
· Units: bytes
· Default: 8k
· Minimum: 40b
Maximum length of any HTTP backend response header we will allow. The
limit is inclusive its continuation lines.
http_resp_size
· Units: bytes
· Default: 8k
· Minimum: 0.25k
Maximum number of bytes of HTTP backend resonse we will deal with.
This is a limit on all bytes up to the double blank line which ends the
HTTP request. The memory for the request is allocated from the worker
workspace (param: thread_pool_workspace) and this parameter limits how
much of that the request is allowed to take up.
idle_send_timeout
· Units: seconds
· Default: 60.000
· Minimum: 0.000
· Flags: delayed
Time to wait with no data sent. If no data has been transmitted in this
many seconds the session is closed. See setsockopt(2) under SO_SND‐
TIMEO for more information.
listen_address
· Default: :80
· Flags: must_restart
Whitespace separated list of network endpoints where Varnish will
accept requests. Possible formats: host, host:port, :port
listen_depth
· Units: connections
· Default: 1024
· Minimum: 0
· Flags: must_restart
Listen queue depth.
lru_interval
· Units: seconds
· Default: 2.000
· Minimum: 0.000
· Flags: experimental
Grace period before object moves on LRU list. Objects are only moved
to the front of the LRU list if they have not been moved there already
inside this timeout period. This reduces the amount of lock operations
necessary for LRU list access.
max_esi_depth
· Units: levels
· Default: 5
· Minimum: 0
Maximum depth of esi:include processing.
max_restarts
· Units: restarts
· Default: 4
· Minimum: 0
Upper limit on how many times a request can restart. Be aware that
restarts are likely to cause a hit against the backend, so don't
increase thoughtlessly.
max_retries
· Units: retries
· Default: 4
· Minimum: 0
Upper limit on how many times a backend fetch can retry.
nuke_limit
· Units: allocations
· Default: 50
· Minimum: 0
· Flags: experimental
Maximum number of objects we attempt to nuke in orderto make space for
a object body.
pcre_match_limit
· Default: 10000
· Minimum: 1
The limit for the number of internal matching function calls in a
pcre_exec() execution.
pcre_match_limit_recursion
· Default: 10000
· Minimum: 1
The limit for the number of internal matching function recursions in a
pcre_exec() execution.
ping_interval
· Units: seconds
· Default: 3
· Minimum: 0
· Flags: must_restart
Interval between pings from parent to child. Zero will disable pinging
entirely, which makes it possible to attach a debugger to the child.
pipe_timeout
· Units: seconds
· Default: 60.000
· Minimum: 0.000
Idle timeout for PIPE sessions. If nothing have been received in either
direction for this many seconds, the session is closed.
pool_req
· Default: 10,100,10
Parameters for per worker pool request memory pool. The three numbers
are:
min_pool
minimum size of free pool.
max_pool
maximum size of free pool.
max_age
max age of free element.
pool_sess
· Default: 10,100,10
Parameters for per worker pool session memory pool. The three numbers
are:
min_pool
minimum size of free pool.
max_pool
maximum size of free pool.
max_age
max age of free element.
pool_vbc
· Default: 10,100,10
Parameters for backend connection memory pool. The three numbers are:
min_pool
minimum size of free pool.
max_pool
maximum size of free pool.
max_age
max age of free element.
pool_vbo
· Default: 10,100,10
Parameters for backend object fetch memory pool. The three numbers
are:
min_pool
minimum size of free pool.
max_pool
maximum size of free pool.
max_age
max age of free element.
prefer_ipv6
· Units: bool
· Default: off
Prefer IPv6 address when connecting to backends which have both IPv4
and IPv6 addresses.
rush_exponent
· Units: requests per request
· Default: 3
· Minimum: 2
· Flags: experimental
How many parked request we start for each completed request on the
object. NB: Even with the implict delay of delivery, this parameter
controls an exponential increase in number of worker threads.
send_timeout
· Units: seconds
· Default: 600.000
· Minimum: 0.000
· Flags: delayed
Send timeout for client connections. If the HTTP response hasn't been
transmitted in this many seconds the session is closed. See setsock‐
opt(2) under SO_SNDTIMEO for more information.
session_max
· Units: sessions
· Default: 100000
· Minimum: 1000
Maximum number of sessions we will allocate from one pool before just
dropping connections. This is mostly an anti-DoS measure, and setting
it plenty high should not hurt, as long as you have the memory for it.
shm_reclen
· Units: bytes
· Default: 255b
· Minimum: 16b
· Maximum: 65535b
Maximum number of bytes in SHM log record. Maximum is 65535 bytes.
shortlived
· Units: s
· Default: 10.000
· Minimum: 0.000
Objects created with (ttl+grace+keep) shorter than this are always put
in transient storage.
sigsegv_handler
· Units: bool
· Default: off
· Flags: must_restart
Install a signal handler which tries to dump debug information on seg‐
mentation faults.
syslog_cli_traffic
· Units: bool
· Default: on
Log all CLI traffic to syslog(LOG_INFO).
tcp_keepalive_intvl
· Units: seconds
· Default: 75.000
· Minimum: 1.000
· Maximum: 100.000
· Flags: experimental
The number of seconds between TCP keep-alive probes.
tcp_keepalive_probes
· Units: probes
· Default: 9
· Minimum: 1
· Maximum: 100
· Flags: experimental
The maximum number of TCP keep-alive probes to send before giving up
and killing the connection if no response is obtained from the other
end.
tcp_keepalive_time
· Units: seconds
· Default: 7200.000
· Minimum: 1.000
· Maximum: 7200.000
· Flags: experimental
The number of seconds a connection needs to be idle before TCP begins
sending out keep-alive probes.
thread_pool_add_delay
· Units: seconds
· Default: 0.000
· Minimum: 0.000
· Flags: experimental
Wait at least this long after creating a thread.
Some (buggy) systems may need a short (sub-second) delay between creat‐
ing threads. Set this to a few milliseconds if you see the
'threads_failed' counter grow too much.
Setting this too high results in insuffient worker threads.
thread_pool_destroy_delay
· Units: seconds
· Default: 1.000
· Minimum: 0.010
· Flags: delayed, experimental
Wait this long after destroying a thread.
This controls the decay of thread pools when idle(-ish).
Minimum is 0.01 second.
thread_pool_fail_delay
· Units: seconds
· Default: 0.200
· Minimum: 0.010
· Flags: experimental
Wait at least this long after a failed thread creation before trying to
create another thread.
Failure to create a worker thread is often a sign that the end is
near, because the process is running out of some resource. This delay
tries to not rush the end on needlessly.
If thread creation failures are a problem, check that thread_pool_max
is not too high.
It may also help to increase thread_pool_timeout and thread_pool_min,
to reduce the rate at which treads are destroyed and later recreated.
thread_pool_max
· Units: threads
· Default: 5000
· Minimum: 100
· Flags: delayed
The maximum number of worker threads in each pool.
Do not set this higher than you have to, since excess worker threads
soak up RAM and CPU and generally just get in the way of getting work
done.
Minimum is 10 threads.
thread_pool_min
· Units: threads
· Default: 100
· Maximum: 5000
· Flags: delayed
The minimum number of worker threads in each pool.
Increasing this may help ramp up faster from low load situations or
when threads have expired.
Minimum is 10 threads.
thread_pool_stack
· Units: bytes
· Default: 48k
· Minimum: 2k
· Flags: experimental
Worker thread stack size. This will likely be rounded up to a multiple
of 4k (or whatever the page_size might be) by the kernel.
thread_pool_timeout
· Units: seconds
· Default: 300.000
· Minimum: 10.000
· Flags: delayed, experimental
Thread idle threshold.
Threads in excess of thread_pool_min, which have been idle for at least
this long, will be destroyed.
Minimum is 10 seconds.
thread_pools
· Units: pools
· Default: 2
· Minimum: 1
· Flags: delayed, experimental
Number of worker thread pools.
Increasing number of worker pools decreases lock contention.
Too many pools waste CPU and RAM resources, and more than one pool for
each CPU is probably detrimal to performance.
Can be increased on the fly, but decreases require a restart to take
effect.
thread_queue_limit
· Default: 20
· Minimum: 0
· Flags: experimental
Permitted queue length per thread-pool.
This sets the number of requests we will queue, waiting for an avail‐
able thread. Above this limit sessions will be dropped instead of
queued.
thread_stats_rate
· Units: requests
· Default: 10
· Minimum: 0
· Flags: experimental
Worker threads accumulate statistics, and dump these into the global
stats counters if the lock is free when they finish a request. This
parameters defines the maximum number of requests a worker thread may
handle, before it is forced to dump its accumulated stats into the
global counters.
timeout_idle
· Units: seconds
· Default: 5.000
· Minimum: 0.000
Idle timeout for client connections. A connection is considered idle,
until we receive a non-white-space character on it.
timeout_linger
· Units: seconds
· Default: 0.050
· Minimum: 0.000
· Flags: experimental
How long time the workerthread lingers on an idle session before hand‐
ing it over to the waiter. When sessions are reused, as much as half
of all reuses happen within the first 100 msec of the previous request
completing. Setting this too high results in worker threads not doing
anything for their keep, setting it too low just means that more ses‐
sions take a detour around the waiter.
timeout_req
· Units: seconds
· Default: 2.000
· Minimum: 0.000
Max time to receive clients request header, measured from first
non-white-space character to double CRNL.
user
· Default: nobody (65534)
· Flags: must_restart
The unprivileged user to run as.
vcc_allow_inline_c
· Units: bool
· Default: off
Allow inline C code in VCL.
vcc_err_unref
· Units: bool
· Default: on
Unreferenced VCL objects result in error.
vcc_unsafe_path
· Units: bool
· Default: on
Allow '/' in vmod & include paths. Allow 'import ... from ...'.
vcl_dir
· Default: /etc/varnish
Directory from which relative VCL filenames (vcl.load and include) are
opened.
vmod_dir
· Default: /usr/lib/varnish/vmods
Directory where VCL modules are to be found.
vsl_buffer
· Units: bytes
· Default: 4k
· Minimum: 1k
Bytes of (req-/backend-)workspace dedicated to buffering VSL records.
At a bare minimum, this must be longer than the longest HTTP header to
be logged. Setting this too high costs memory, setting it too low will
cause more VSL flushes and likely increase lock-contention on the VSL
mutex. Minimum is 1k bytes.
vsl_mask
· Default: -VCL_trace,-WorkThread,-Hash
Mask individual VSL messages from being logged.
default
Set default value
Use +/- prefixe in front of VSL tag name, to mask/unmask individual VSL
messages.
vsl_space
· Units: bytes
· Default: 80M
· Minimum: 1M
· Flags: must_restart
The amount of space to allocate for the VSL fifo buffer in the VSM mem‐
ory segment. If you make this too small, varnish{ncsa|log} etc will
not be able to keep up. Making it too large just costs memory
resources.
vsm_space
· Units: bytes
· Default: 1M
· Minimum: 1M
· Flags: must_restart
The amount of space to allocate for stats counters in the VSM memory
segment. If you make this too small, some counters will be invisible.
Making it too large just costs memory resources.
waiter
· Default: epoll (possible values: epoll, poll)
· Flags: must_restart, wizard
Select the waiter kernel interface.
workspace_backend
· Units: bytes
· Default: 16k
· Minimum: 1k
· Flags: delayed
Bytes of HTTP protocol workspace for backend HTTP req/resp. If larger
than 4k, use a multiple of 4k for VM efficiency.
workspace_client
· Units: bytes
· Default: 24k
· Minimum: 3k
· Flags: delayed
Bytes of HTTP protocol workspace for clients HTTP req/resp. If larger
than 4k, use a multiple of 4k for VM efficiency.
workspace_session
· Units: bytes
· Default: 384b
· Minimum: 0.25k
· Flags: delayed
Bytes of workspace for session and TCP connection addresses. If larger
than 4k, use a multiple of 4k for VM efficiency.
workspace_thread
· Units: bytes
· Default: 2k
· Minimum: 0.25k
· Maximum: 8k
· Flags: delayed
Bytes of auxillary workspace per thread. This workspace is used for
certain temporary data structures during the operation of a worker
thread. One use is for the io-vectors for writing requests and
responses to sockets, having too little space will result in more
writev(2) system calls, having too much just wastes the space.
SEE ALSO
· varnish-cli(7)
· varnishlog(1)
· varnishhist(1)
· varnishncsa(1)
· varnishstat(1)
· varnishtop(1)
· vcl(7)HISTORY
The varnishd daemon was developed by Poul-Henning Kamp in cooperation
with Verdens Gang AS and Varnish Software.
This manual page was written by Dag-Erling Smørgrav with updates by
Stig Sandbeck Mathisen <ssm@debian.org>.
COPYRIGHT
This document is licensed under the same licence as Varnish itself. See
LICENCE for details.
· Copyright (c) 2007-2014 Varnish Software AS
VARNISHD()
