Similarly to the previous commit, we get rid of unused peer member.
peer->addr was only used to save a copy of the sever's addr at parsing
time. But instead of relying on an intermediate variable, we can actually
use server's address directly when initiating the peer session.
As with other streams created from server's settings (tcp/http, log, ring),
we should rely on srv->svc_port for the port part of the address. This
shouldn't change anything for peers since the address is fully resolved
at parsing time and runtime changes are not supported, but this should
help to make the code future-proof.
peer->proto and peer->xprt struct members are now pure legacy: they are
only set during parsing but never used afterwards.
This is due to commit 02efedac ("MINOR: peers: now remove the remote
connection setup code") which made some cleanup in the past, but the
unused proto and xprt members were probably left unused by mistake.
Since we don't have valid uses for them, we remove them.
Also, peer_xprt() helper function was removed since it was related to
peer->xprt struct member.
The number of updates sent at once was limited to not loop too long to emit
updates when the buffer size is huge or when the number of sync tables is
huge. The limit can be configured and is set to 200 by default. However,
this fix introduced a bug. It is impossible to syncrhonize two peers if the
number of tables is higher than this limit. Thus by default, it is not
possible to sync two peers if there are more than 200 tables to sync.
Technically speacking, a teaching process is finished if we loop on all tables
with no new update messages sent. Because we are limited at each call, the loop
is splitted on several calls. However the restart point for the next loop is
always the last table for which we emitted an update message. Thus with more
tables than the limit, the loop never reachs the end point.
Worse, in conjunction with the bug fixed by "BUG/MEDIUM: peers: Be sure to
always refresh recconnect timer in sync task", it is possible to trigger the
watchdog because the applets may be woken up in loop and leave requesting
more room while its buffer is empty.
To fix the issue, restart conditions for a teaching loop were changed. If
the teach process is interrupted, we now save the restart point, called
stop_local_table. It is the last evaluated table on the previous loop. This
restart point is reset when the teach process is finished.
In additionn, the updates_sent variable in peer_send_msgs() was renamed to
updates to avoid ambiguities. Indeed, the variable is incremented, whether
messages were sent or not.
This patch must be backported as far as 2.6.
peers-t.h uses "struct stktable" as well as STKTABLE_DATA_TYPES which
are defined in stick-table-t.h. It works by accident because
stick-table-t.h was always included before. But could provoke build
issue with EXTRA code.
To be backported as far as 2.2.
Add "shards" new keyword for "peers" section to configure the number
of peer shards attached to such secions. This impact all the stick-tables
attached to the section.
Add "shard" new "server" parameter to configure the peers which participate to
all the stick-tables contents distribution. Each peer receive the stick-tables updates
only for keys with this shard value as distribution hash. The "shard" value
is stored in ->shard new server struct member.
cfg_parse_peers() which is the function which is called to parse all
the lines of a "peers" section is modified to parse the "shards" parameter
stored in ->nb_shards new peers struct member.
Add srv_parse_shard() new callback into server.c to pare the "shard"
parameter.
Implement stksess_getkey_hash() to compute the distribution hash for a
stick-table key as the 64-bits xxhash of the key concatenated to the stick-table
name. This function is called by stksess_setkey_shard(), itself
called by the already implemented function which create a new stick-table
key (stksess_new()).
Add ->idlen new stktable struct member to store the stick-table name length
to not have to compute it each time a stick-table key hash is computed.
No need to include the full tree management code, type files only
need the definitions. Doing so reduces the whole code size by around
3.6% and the build time is down to just 6s.
This patch adds support of array data_types on the peer protocol.
The table definition message will provide an additionnal parameter
for array data-types: the number of elements of the array.
In case of array of frqp it also provides a second parameter:
the period used to compute freq counter.
The array elements are std_type values linearly encoded in
the update message.
Note: if a remote peer announces an array data_type without
parameters into the table definition message, all updates
on this table will be ignored because we can not
parse update messages consistently.
A few structures were slightly rearranged in order to plug some holes
left around the locks. Sizes ranging from 8 to 32 bytes could be saved
depending on the structures. No performance difference was noticed (none
was expected there), though memory usage might be slightly reduced in
some rare cases.
This patch adds "coll" new counter and the heartbeat timer values to "show peers"
command. It also adds the elapsed time since the last handshake to new "last_hdshk"
new peer dump field.
The enabled/disabled config options were stored into a "state" field
that is an integer but contained only PR_STNEW or PR_STSTOPPED, which
is a bit confusing, and causes a dependency with proxies. This was
renamed to "disabled" and is used as a boolean. The field was also
moved to the end of the struct to stop creating a hole and fill another
one.
There are list definitions everywhere in the code, let's drop the need
for including list-t.h to declare them. The rest of the list manipulation
is huge however and not needed everywhere so using the list walking macros
still requires to include list.h.
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
The cfg_peers external declaration was moved to the main file instead
of the type one. A few types were still missing from the proto, causing
warnings in the functions prototypes (proxy, stick_table).