Finn Arne Gangstad suggested that we should have the ability to break
keep-alive when the target server has reached its maxconn and that a
number of connections are present in the queue. After some discussion
around his proposed patch, the following solution was suggested : have
a per-proxy setting to fix a limit to the number of queued connections
on a server after which we break keep-alive. This ensures that even in
high latency networks where keep-alive is beneficial, we try to find a
different server.
This patch is partially based on his original proposal and implements
this configurable threshold.
All the code inherited from version 1.1 still holds a lot ot sessions
called "t" because in 1.1 they were tasks. This naming is very annoying
and sometimes even confusing, for example in code involving tables.
Let's get rid of this once for all and before 1.5-final.
Nothing changed beyond just carefully renaming these variables.
This basically reimplements commit f3221f9 ("MEDIUM: stats: add support
for HTTP keep-alive on the stats page") which was reverted by commit
51437d2 after Igor Chan reported a broken stats page caused by the bug
fix by previous commit.
In order to avoid abusively relying on buf->o to guess how many bytes to
rewind during a redispatch, we now clear msg->sov. Thus the meaning of this
field is exactly "how many bytes of headers are left to be forwarded". It
is still possible to rewind because msg->eoh + msg->eol equal that value
before scheduling the forwarding, so we can always subtract them.
http_body_rewind() returns the number of bytes to rewind before buf->p to
find the message's body. It relies on http_hdr_rewind() to find the beginning
and adds msg->eoh + msg->eol which are always safe.
http_data_rewind() does the same to get the beginning of the data, which
differs from above when a chunk is present. It uses the function above and
adds msg->sol.
The purpose is to centralize further ->sov changes aiming at avoiding
to rely on buf->o.
http_uri_rewind() returns the number of bytes to rewind before buf->p to
find the URI. It relies on http_hdr_rewind() to find the beginning and
is just here to simplify operations.
The purpose is to centralize further ->sov changes aiming at avoiding
to rely on buf->o.
http_hdr_rewind() returns the number of bytes to rewind before buf->p to
find the beginning of headers. At the moment it's not exact as it still
relies on buf->o, assuming that no other data from a past message were
pending there, but it's what was done till there.
The purpose is to centralize further ->sov changes aiming at avoiding
to rely on buf->o.
http_body_bytes() returns the number of bytes of the current message body
present in the buffer. It is compatible with being called before and after
the headers are forwarded.
This is done to centralize further ->sov changes.
The function addr_to_stktable_key doesn't consider the expected
type of key. If the stick table key is based on IPv6 addresses
and the input is IPv4, the returned key is IPv4 adddress and his
length is 4 bytes, while is expected 16 bytes key.
This patch considers the expected key and try to convert IPv4 to
IPv6 and IPv6 to IPv4 according with the expected key.
This fixes the bug reported by Apollon Oikonomopoulos.
This bug was introduced somewhere in the 1.5-dev process.
The cfgparse.c file becomes huge, and a large part of it comes from the
server keyword parser. Since the configuration is a bit more modular now,
move this parser to server.c.
This patch also moves the check of the "server" keyword earlier in the
supported keywords list, resulting in a slightly faster config parsing
for configs with large numbers of servers (about 10%).
No functional change was made, only the code was moved.
This function it is used for dynamically update all the patterns
attached to one file. This function is atomic. All parsing or indexation
failures are reported in the haproxy logs.
This patch adds new display type. This display returns allocated string,
when the string is flush into buffers, it is freed. This permit to
return the content of "memprintf(err, ...)" messages.
The pat_ref_add functions has changed to return error.
The acl and map function do the same work with the file parsing. This
patch merge these code in only one.
Note that the function map_read_entries_from_file() in the file "map.c"
is moved to the the function pat_ref_read_from_file_smp() in the file
"pattern.c". The code of this function is not modified, only the the
name and the arguments order has changed.
The find_smp search the smp using the value of the pat_ref_elt pointer.
The pat_find_smp_* are no longer used. The function pattern_find_smp()
known all pattern indexation, and can be found
All the pattern delete function can use her reference to the original
"struct pat_ref_elt" to find the element to be remove. The functions
pat_del_list_str() and pat_del_meth() were deleted because after
applying this modification, they have the same code than pat_del_list_ptr().
The pattern reference are stored with two identifiers: the unique_id and
the reference.
The reference identify a file. Each file with the same name point to the
same reference. We can register many times one file. If the file is
modified, all his dependencies are also modified. The reference can be
used with map or acl.
The unique_id identify inline acl. The unique id is unique for each acl.
You cannot force the same id in the configuration file, because this
repport an error.
The format of the acl and map listing through the "socket" has changed
for displaying these new ids.
This patch extract the expect_type variable from the "struct pattern" to
"struct pattern_head". This variable is set during the declaration of
ACL and MAP. With this change, the function "pat_parse_len()" become
useless and can be replaced by "pat_parse_int()".
Implicit ACLs by default rely on the fetch's output type, so let's simply do
the same for all other ones. It has been verified that they all match.
This patch add the following socket command line options:
show acl [<id>]
clear acl <id>
get acl <id> <pattern>
del acl <id> <pattern>
add acl <id> <pattern>
The system used for maps is backported in the pattern functions.
Some functions needs to change the sample associated to pattern. This
new pointer permit to return the a pointer to the sample pointer. The
caller can use or change the value.
This commit adds a delete function for patterns. It looks up all
instances of the pattern to delete and deletes them all. The fetch
keyword declarations have been extended to point to the appropriate
delete function.
The match function known the format of the pattern. The pattern can be
stored in a list or in a tree. The pattern matching function use itself
the good entry point and indexation type.
Each pattern matching function return the struct pattern that match. If
the flag "fill" is set, the struct pattern is filled, otherwise the
content of this struct must not be used.
With this feature, the general pattern matching function cannot have
exceptions for building the "struct pattern".
Before this commit, the pattern_exec_match() function returns the
associate sample, the associate struct pattern or the associate struct
pattern_tree. This is complex to use, because we can check the type of
information returned.
Now the function return always a "struct pattern". If <fill> is not set,
only the value of the pointer can be used as boolean (NULL or other). If
<fill> is set, you can use the <smp> pointer and the pattern
information.
If information must be duplicated, it is stored in trash buffer.
Otherwise, the pattern can point on existing strings.
The method are actuelly stored using two types. Integer if the method is
known and string if the method is not known. The fetch is declared as
UINT, but in some case it can provides STR.
This patch create new type called METH. This type contain interge for
known method and string for the other methods. It can be used with
automatic converters.
The pattern matching can expect method.
During the free or prune function, http_meth pettern is freed. This
patch initialise the freed pointer to NULL.
The operations applied on types SMP_T_CSTR and SMP_T_STR are the same,
but the check code and the declarations are double, because it must
declare action for SMP_T_C* and SMP_T_*. The declared actions and checks
are the same. this complexify the code. Only the "conv" functions can
change from "C*" to "*"
Now, if a function needs to modify input string, it can call the new
function smp_dup(). This one duplicate data in a trash buffer.
The pattern parse functions put the parsed result in a "struct pattern"
without memory allocation. If the pattern must reference the input data
without changes, the pattern point to the parsed string. If buffers are
needed to store translated data, it use th trash buffer. The indexation
function that allocate the memory later if it is needed.
Before this patch, the indexation function check the declared patttern
matching function and index the data according with this function. This
is not useful to add some indexation mode.
This commit adds dedicated indexation function. Each struct pattern is
associated with one indexation function. This function permit to index
data according with the type of pattern and with the type of match.
This commit separes the "struct list" used for the chain the "struct
pattern" which contain the pattern data. Later, this change will permit
to manipulate lists ans trees with the same "struct pattern".
Each pattern parser take only one string. This change is reported to the
function prototype of the function "pattern_register()". Now, it is
called with just one string and no need to browse the array of args.
After the previous patches, the "pat_parse_strcat()" function disappear,
and the "pat_parse_int()" and "pat_parse_dotted_ver()" functions dont
use anymore the "opaque" argument, and take only one string on his
input.
So, after this patch, each pattern parser no longer use the opaque
variable and take only one string as input. This patch change the
prototype of the pattern parsing functions.
Now, the "char **args" is replaced by a "char *arg", the "int *opaque"
is removed and these functions return 1 in succes case, and 0 if fail.
This patch remove the limit of 32 groups. It also permit to use standard
"pat_parse_str()" function in place of "pat_parse_strcat()". The
"pat_parse_strcat()" is no longer used and its removed. Before this
patch, the groups are stored in a bitfield, now they are stored in a
list of strings. The matching is slower, but the number of groups is
low and generally the list of allowed groups is short.
The fetch function "smp_fetch_http_auth_grp()" used with the name
"http_auth_group" return valid username. It can be used as string for
displaying the username or with the acl "http_auth_group" for checking
the group of the user.
Maybe the names of the ACL and fetch methods are no longer suitable, but
I keep the current names for conserving the compatibility with existing
configurations.
The function "userlist_postinit()" is created from verification code
stored in the big function "check_config_validity()". The code is
adapted to the new authentication storage system and it is moved in the
"src/auth.c" file. This function is used to check the validity of the
users declared in groups and to check the validity of groups declared
on the "user" entries.
This resolve function is executed before the check of all proxy because
many acl needs solved users and groups.
Large configurations can take time to parse when thousands of backends
are in use. Let's store all the proxies in trees.
findproxy_mode() has been modified to use the tree for lookups, which
has divided the parsing time by about 2.5. But many lookups are still
present at many places and need to be dealt with.
We store the time stamp of last read in the channel in order to
be able to measure some bit rate and pause lengths. We only use
16 bits which were unused for this. We don't need more, as it
allows us to measure with a millisecond precision for up to 65s.
These ones are only reset during transfers. There is a low but non-null
risk that a first full read causes the previous value to be reused and
immediately to immediately set the CF_STREAMER flag. The impact is only
to increase earlier than expected the SSL record size and to use splice().
This bug was already present in 1.4, so a backport is possible.
Summary:
Track and report last session time on the stats page for each server
in every backend, as well as the backend.
This attempts to address the requirement in the ROADMAP
- add a last activity date for each server (req/resp) that will be
displayed in the stats. It will be useful with soft stop.
The stats page reports this as time elapsed since last session. This
change does not adequately address the requirement for long running
session (websocket, RDP... etc).
Till now, we had one flag per stick counter to indicate if it was
tracked in a backend or in a frontend. We just had to add another
flag per stick-counter to indicate if it relies on contents or just
connection. These flags are quite painful to maintain and tend to
easily conflict with other flags if their number is changed.
The correct solution consists in moving the flags to the stkctr struct
itself, but currently this struct is made of 2 pointers, so adding a
new entry there to store only two bits will cause at least 16 more bytes
to be eaten per counter due to alignment issues, and we definitely don't
want to waste tens to hundreds of bytes per session just for things that
most users don't use.
Since we only need to store two bits per counter, an intermediate
solution consists in replacing the entry pointer with a composite
value made of the original entry pointer and the two flags in the
2 unused lower bits. If later a need for other flags arises, we'll
have to store them in the struct.
A few inline functions have been added to abstract the retrieval
and assignment of the pointers and flags, resulting in very few
changes. That way there is no more dependence on the number of
stick-counters and their position in the session flags.
One year ago, commit 5d5b5d8 ("MEDIUM: proto_tcp: add support for tracking
L7 information") brought support for tracking L7 information in tcp-request
content rules. Two years earlier, commit 0a4838c ("[MEDIUM] session-counters:
correctly unbind the counters tracked by the backend") used to flush the
backend counters after processing a request.
While that earliest patch was correct at the time, it became wrong after
the second patch was merged. The code does what it says, but the concept
is flawed. "TCP request content" rules are evaluated for each HTTP request
over a single connection. So if such a rule in the frontend decides to
track any L7 information or to track L4 information when an L7 condition
matches, then it is applied to all requests over the same connection even
if they don't match. This means that a rule such as :
tcp-request content track-sc0 src if { path /index.html }
will count one request for index.html, and another one for each of the
objects present on this page that are fetched over the same connection
which sent the initial matching request.
Worse, it is possible to make the code do stupid things by using multiple
counters:
tcp-request content track-sc0 src if { path /foo }
tcp-request content track-sc1 src if { path /bar }
Just sending two requests first, one with /foo, one with /bar, shows
twice the number of requests for all subsequent requests. Just because
both of them persist after the end of the request.
So the decision to flush backend-tracked counters was not the correct
one. In practice, what is important is to flush countent-based rules
since they are the ones evaluated for each request.
Doing so requires new flags in the session however, to keep track of
which stick-counter was tracked by what ruleset. A later change might
make this easier to maintain over time.
This bug is 1.5-specific, no backport to stable is needed.
