Commit 08e9e5337383 fixed proper initialization of the dns-resolve
module, and made DNS resolution asynchronous.
A side effect of that change revealed a long standing logic bug
which broke ovsdb-server listener configuration using DNS names.
Previously this worked because the DNS resolution would block,
now that DNS resolution is asynchronous the code before this
change would assume the error from jsonrpc_pstream_open meant
the remote was a specification for an active outgoing
connection, even when that was not the case.
To fix this a couple of changes was made to socket-util:
1) Pass optional result of dns resolution from inet_parse_passive.
When (re-)configuring listeners that use DNS names, we may need
to know whether the provided connection string is invalid or if
the provided DNS name has finished resolving.
2) Check dns resolution status in inet_open_passive.
If the connection string is valid, and contains a DNS name,
inet_open_passive will now return -EAGAIN if dns resolution
failed. DNS resolution failure may either mean the asynchronous
resolver has not completed yet, or that the name does not resolve.
Reported-at: https://bugs.launchpad.net/bugs/1998781
Fixes: 08e9e5337383 ("ovsdb: raft: Fix inability to read the database with DNS host names.")
Fixes: 771680d96fb6 ("DNS: Add basic support for asynchronous DNS resolving")
Signed-off-by: Frode Nordahl <frode.nordahl@canonical.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Using SHORT version of the *_SAFE loops makes the code cleaner and less
error prone. So, use the SHORT version and remove the extra variable
when possible for hmap and all its derived types.
In order to be able to use both long and short versions without changing
the name of the macro for all the clients, overload the existing name
and select the appropriate version depending on the number of arguments.
Acked-by: Dumitru Ceara <dceara@redhat.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Using the SHORT version of the *_SAFE loops makes the code cleaner
and less error-prone. So, use the SHORT version and remove the extra
variable when possible.
In order to be able to use both long and short versions without changing
the name of the macro for all the clients, overload the existing name
and select the appropriate version depending on the number of arguments.
Acked-by: Dumitru Ceara <dceara@redhat.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
If there are completed triggers, jsonrpc server should wake up and
update clients with the new data, but there is no such condition
in ovsdb_jsonrpc_session_wait(). For some reason this doesn't result
in any processing delays in current code, probably because there are
always some other types of events in this case that could wake ovsdb
server up. But it will become a problem in upcoming ovsdb 'relay'
service model because triggers could be completed from a different
place, i.e. after receiving transaction reply from the relay source.
Fix that by waking up ovsdb-server in case there are completed triggers
that needs to be handled.
Acked-by: Mark D. Gray <mark.d.gray@redhat.com>
Acked-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
The commit [1] force drops all connections when the db read/write status changes.
Prior to the commit [1], when there was read/write status change, the existing
jsonrpc sessions with 'db_change_aware' set to true, were not updated with the
changed 'read_only' value. If the db status was changed to 'standby', the existing
clients could still write to the db.
In the case of pacemaker OVN HA, OVN OCF script 'start' action starts the
ovsdb-servers in read-only state and later, it sets to read-write in the
'promote' action. We have observed that if some ovn-controllers connect to
the SB ovsdb-server (in read-only state) just before the 'promote' action,
the connection is not reset all the times and these ovn-controllers remain connected
to the SB ovsdb-server in read-only state all the time. Even though
the commit [1] calls 'ovsdb_jsonrpc_server_reconnect()' with 'forced' flag
set to true when the db read/write status changes, somehow the FSM misses resetting
the connections of these ovn-controllers.
I think this needs to be addressed in the FSM. This patch doesn't address
this FSM issue. Instead it changes the behavior of 'ovsdb_jsonrpc_server_set_read_only()'
by setting the 'read_only' flag of all the jsonrpc sessions instead of forcefully
resetting the connection.
I think there is no need to reset the connection. In large scale production
deployements with OVN, this results in unnecessary waste of CPU cycles as ovn-controllers
will have to connect twice - once during 'start' action and again during 'promote'.
[1] - 2a9679e3b2c6("ovsdb-server: drop all connections on read/write status change")
Acked-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Numan Siddique <nusiddiq@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Prior to this patch, only db change aware connections were dropped
on a read/write status change. However, current schema in OVN does
not allow clients to monitor whether a particular DB changes this
status. In order to accomplish this, we'd need to change the schema
and adapting ovsdb-server and existing clients.
Before tackling that, this patch is changing ovsdb-server to drop
*all* the existing connections upon a read/write status change. This
will force clients to reconnect and honor the change.
Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2019-July/048981.html
Signed-off-by: Daniel Alvarez <dalvarez@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Support the new monitor method monitor_cond_since so that a client
can request monitoring start from a specific point instead of always
from beginning. This will reduce the cost at scenarios when server
is restarted/failed-over but client still has all existing data. In
these scenarios only new changes (and in most cases no change) needed
to be transfered to client. When ovsdb-server restarted, history
transactions are read from disk file; when ovsdb-server failed over,
history transactions exists already in the memory of the new server.
There are situations that the requested transaction may not be found.
For example, a transaction that is too old and has been discarded
from the maintained history list in memory, or the transactions on
disk has been compacted during ovsdb compaction. In those situations
the server fall backs to transfer all data start from begining.
For more details of the protocol change, see
Documentation/ref/ovsdb-server.7.rst.
This change includes both server side and ovsdb-client side changes
with the new protocol. IDLs using this capability will be added in
future patches.
Now the feature takes effect only for cluster mode of ovsdb-server,
because cluster mode is the only mode that supports unique transcation
uuid today. For other modes, the monitor_cond_since always fall back
to transfer all data with found = false. Support for those modes can
be added in the future.
Signed-off-by: Han Zhou <hzhou8@ebay.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Current ovsdb monitor maintains its own transaction version through an
incremental integer and use it to identify changes starting from different
version, and also use it to figure out if each set of changes should be
flushed. In particular, it uses number 0 to represent that the change set
contains all data for initial client population. It is a smart way but it
prevents further extension of the monitoring mechanism to support future use
case for clients to request changes starting from a given history point. This
patch refactors the structures so that change sets are referenced directly
through the pointer. It uses additional members such as init_change_set,
new_change_set to indicates the specific change set explicitely, instead of
through calculated version numbers based on implicite rules.
At the same time, this patch provides better encapsulation for change set
(composed of data in a list of tables), while still allowing traversing
across change sets for a given table.
Signed-off-by: Han Zhou <hzhou8@ebay.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Ommiting the parameter names in prototypes, as suggested by coding
style: Omit parameter names from function prototypes when the names
do not give useful information.
Adjust orders of parameters as suggested by coding style.
Signed-off-by: Han Zhou <hzhou8@ebay.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
When ovsdb-server closes a remote connection, it logs a message about it
that includes the reason. Until now this has included sessions that it
closes when it exits. That meant that, when --run was used, there was a
race between noticing that the subprocess exited and noticing that the
session that that subprocess (presumably) had open had been closed. If
it noticed the latter first, nothing was logged (because it didn't log
anything if a session was closed in the ordinary way by the client). If
it noticed the former first, it logged a message about closing the session
itself.
This is a benign race that causes no real problems--except that the tests
didn't expect to see the log message from the former case and fail with
errors like the following:
1826. ovsdb-server.at:92: testing truncating database log with bad transaction ...
./ovsdb-server.at:96: ovsdb-tool create db schema
stderr:
stdout:
./ovsdb-server.at:104: ovsdb-server --remote=punix:socket db --run="sh txnfile"
--- /dev/null 2018-04-24 08:50:58.769000000 +0000
+++ /root/openvswitch-2.9.2/rpm/rpmbuild/BUILD/openvswitch-2.9.2/tests/testsuite.dir/at-groups/1826/stderr 2018-05-29 14:29:56.529257295 +0000
@@ -0,0 +1,2 @@
+2018-05-29T14:29:56Z|00001|ovsdb_jsonrpc_server|INFO|unix#0: disconnecting (removing ordinals database due to server termination)
+2018-05-29T14:29:56Z|00002|ovsdb_jsonrpc_server|INFO|unix#0: disconnecting (removing _Server database due to server termination)
This fixes the race. This particular log message isn't too useful since
it's pretty obvious that ovsdb-server is closing those sessions, since
after all it's exiting!
Reported-by: Sanket Sudake <sanket@infracloud.io>
Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2018-May/046840.html
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Numan Siddique <nusiddiq@redhat.com>
Several OVS structs contain embedded named unions, like this:
struct {
...
union {
...
} u;
};
C11 standardized a feature that many compilers already implemented
anyway, where an embedded union may be unnamed, like this:
struct {
...
union {
...
};
};
This is more convenient because it allows the programmer to omit "u."
in many places. OVS already used this feature in several places. This
commit embraces it in several others.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
Tested-by: Alin Gabriel Serdean <aserdean@ovn.org>
Acked-by: Alin Gabriel Serdean <aserdean@ovn.org>
This commit adds support for OVSDB clustering via Raft. Please read
ovsdb(7) for information on how to set up a clustered database. It is
simple and boils down to running "ovsdb-tool create-cluster" on one server
and "ovsdb-tool join-cluster" on each of the others and then starting
ovsdb-server in the usual way on all of them.
One you have a clustered database, you configure ovn-controller and
ovn-northd to use it by pointing them to all of the servers, e.g. where
previously you might have said "tcp:1.2.3.4" was the database server,
now you say that it is "tcp:1.2.3.4,tcp:5.6.7.8,tcp:9.10.11.12".
This also adds support for database clustering to ovs-sandbox.
Acked-by: Justin Pettit <jpettit@ovn.org>
Tested-by: aginwala <aginwala@asu.edu>
Signed-off-by: Ben Pfaff <blp@ovn.org>
With this change, "ovsdb-client convert" can be used to convert a database
from one schema to another without taking the database offline.
This can be useful to minimize downtime for a database during a software
upgrade.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
The _Server database recently added to ovsdb-server can be used to dump out
information about databases, but monitoring updates to _Server is not yet
very useful because for historical reasons ovsdb-server drops all of its
OVSDB connections whenever databases are added or removed or otherwise
change in some major way. It is not a good idea to change this behavior
for all clients, because some of them rely on it, but this commit
introduces a new RPC that allows clients that understand _Server to
suppress the connection-closing behavior.
Signed-off-by: Ben Pfaff <blp@ovn.org>
The code in jsonrpc-server conflated two different kinds of functionality.
It makes sense for the client to be able to change whether a particular
server is read-only. It also makes sense for the client to tell a server
to reconnect. The code in jsonrpc-server only provided a single function
that does both, which is weird. This commit breaks these apart.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
This oversight allowed monitor IDs to be duplicated when the
monitor_cond_change request changed them.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
This simplifies little bits of code here and there.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Tested-by: Yifeng Sun <pkusunyifeng@gmail.com>
Reviewed-by: Yifeng Sun <pkusunyifeng@gmail.com>
The error message in question is about the monitor session ID but it
actually reports the JSON-RPC request ID instead, which is surprising.
Found by inspection.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Justin Pettit <jpettit@ovn.org>
Poll-loop is the core to implement main loop. It should be available in
libopenvswitch.
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Shadowing is when a variable with a given name in an inner scope hides a
different variable with the same name in a surrounding scope. This is
generally undesirable because it can confuse programmers. This commit
eliminates most of it.
Found with -Wshadow=local in GCC 7. The repo is not really ready to enable
this option by default because of a few cases that are harder to fix, and
harmless, such as nested use of CMAP_FOR_EACH.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Andy Zhou <azhou@ovn.org>
Add suport for ovsdb RBAC (role-based access control). This includes:
- Support for "RBAC_Role" table. A db schema containing a table
by this name will enable role-based access controls using
this table for RBAC role configuration.
The "RBAC_Role" table has one row per role, with each row having a
"name" column (role name) and a "permissions" column (map of
table name to UUID of row in separate permission table.) The
permission table has one row per access control configuration,
with the following columns:
"name" - name of table to which this row applies
"authorization" - set of column names and column:key pairs
to be compared against client ID to
determine authorization status
"insert_delete" - boolean, true if insertions and
authorized deletions are allowed.
"update" - Set of columns and column:key pairs for
which authorized updates are allowed.
- Support for a new "role" column in the remote configuration
table.
- Logic for applying the RBAC role and permission tables, in
combination with session role from the remote connection table
and client id, to determine whether operations modifying database
contents should be permitted.
- Support for specifying RBAC role string as a command-line option
to ovsdb-tool (Ben Pfaff).
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Co-authored-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Replication OVSDB server from itself is usually caused by configuration
errors. Such configuration errors can lead to OVSDB server data loss.
See "reported-at" for more details.
This patch adds logics that prevent OVSDB server from replicating
itself.
Reported-by: Guishuai Li <ligs@dtdream.com>
Reported-at: https://mail.openvswitch.org/pipermail/ovs-dev/2017-January/326963.html
Suggested-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Currently, there is no way for an OVSDB server to ID itself. This patch
adds a UUID field that is populated every time OVSDB server runs.
Later patch will make use this UUID to detect and stop and OVSDB server
from replicating itself.
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Adds a new "read_only" column for remote connections.
Operations that would alter the state of the database are not
permitted on connections for which the "read_only" column is set
to "true".
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
By placing these nodes at the start of their respective structures,
several "possibly lost" warnings from valgrind are silenced.
Fixes: 60e0cd041958 ("ovsdb: Replication usability improvements")
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Based on feedbacks from initial HA manager integration, added the
'--active' command line option and appctl command
"ovsdb-server/sync-status. See man page updates for details.
Added the RPL_S_INIT state in the state machine. This state is
not strictly necessary for the replication state machine, but is
introduced to make sure the state is update immediately when
the state machine is reset, via replication_init(). Without it
ovsdb/sync-status may display "replicating" or crash, if the command
is issued between after replication_init() is called, but before
the state variable is updated from replication_run().
Added a test to simulate the integration of HA manager with OVSDB
server using replication.
Other documentation and API improvements.
Tested-by: Numan Siddique <nusiddiq@redhat.com>
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
When ovsdb-sever is running in the backup state, it would be nice to
make sure there is no un-intended changes to the backup database.
This patch makes the ovsdb server only accepts 'read' transactions as
a backup server. When the server role is changed into an active server,
all existing client connections will be reset. After reconnect, all
clinet transactions will then be accepted.
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
To easily allow both in- and out-of-tree building of the Python
wrapper for the OVS JSON parser (e.g. w/ pip), move json.h to
include/openvswitch. This also requires moving lib/{hmap,shash}.h.
Both hmap.h and shash.h were #include-ing "util.h" even though the
headers themselves did not use anything from there, but rather from
include/openvswitch/util.h. Fixing that required including util.h
in several C files mostly due to OVS_NOT_REACHED and things like
xmalloc.
Signed-off-by: Terry Wilson <twilson@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Add monitor_cond method to ovsdb-client. Enable testing of monitor_cond_change
via unixctl command.Add unit tests for monitor_cond and monitor_cond_change.
See ovsdb-client(1) man page for details.
Replace monitor2 with monitor_cond.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
ovsdb-server now accepts "monitor_cond_change" request. After conditions change
we compose update notification according to the current state of the
database without using a change list before sending reply to the monitor_cond_change
request.
Sees ovsdb-server (1) man page for details of monitor_cond_change.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Hold session's conditions in ovsdb_monitor_session_condition. Pass it
to ovsdb_monitor for generating "update2" notifications.
Add functions that can generate "update2" notification for a
"monitor_cond" session.
JSON cache is enabled only for session's with true condition only.
"monitor_cond" and "monitor_cond_change" are RFC 7047 extensions
described by ovsdb-server(1) manpage.
Performance evaluation:
OVN is the main candidate for conditional monitoring usage. It is clear that
conditional monitoring reduces computation on the ovn-controller (client) side
due to the reduced size of flow tables and update messages. Performance
evaluation shows up to 75% computation reduction.
However, performance evaluation shows also a reduction in computation on the SB
ovsdb-server side proportional to the degree that each logical network is
spread over physical hosts in the DC. Evaluation shows that in a realistic
scenarios there is a computation reduction also in the server side.
Evaluation on simulated environment of 50 hosts and 1000 logical ports shows
the following results (cycles #):
LN spread over # hosts| master | patch | change
-------------------------------------------------------------
1 | 24597200127 | 24339235374 | 1.0%
6 | 23788521572 | 19145229352 | 19.5%
12 | 23886405758 | 17913143176 | 25.0%
18 | 25812686279 | 23675094540 | 8.2%
24 | 28414671499 | 24770202308 | 12.8%
30 | 31487218890 | 28397543436 | 9.8%
36 | 36116993930 | 34105388739 | 5.5%
42 | 37898342465 | 38647139083 | -1.9%
48 | 41637996229 | 41846616306 | -0.5%
50 | 41679995357 | 43455565977 | -4.2%
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
This commit allows to add unmonitored columns to a monitored table
due to condition update.
It will be used to evaluate conditions on unmonitored columns.
Update notification includes only monitored columns.
Due to the limited number of columns, we do not remove unused unmonitored
columns on condition update for code simplicity.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Columns indexing is different in ovsdb_row then in ovsdb_monitor_row.
We need mapping between the 2 for condition evaluation.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
This attempts to prevent namespace collisions with other list libraries
Signed-off-by: Ben Warren <ben@skyportsystems.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
When destroying an ovsdb_jsonrpc_monitor, the jsonrpc monitor still
holds a reference count to the monitors 'changes' indexed with
'unflushed' transaction id. The bug is that the reference count was
not decremented as it should in the code path.
The bug caused 'changes' that have been flushed to all jsonrpc
clients to linger around unnecessarily, occupying increasingly
large amount of memory. See "Reported-at" URL for more details.
This bug is tricky to find since the memory is not leaked; they will
eventually be freed when monitors are destroyed.
Reported-by: Lei Huang <huang.f.lei@gmail.com>
Reported-at: http://openvswitch.org/pipermail/dev/2016-March/067274.html
Signed-off-by: Andy Zhou <azhou@ovn.org>
Tested-by: Han Zhou <zhouhan@gmail.com>
Acked-by: Han Zhou <zhouhan@gmail.com>
Acked-by: Liran Schour <lirans@il.ibm.com>
When reporting remote status, A listening remote will randomly
pick a session and report its session status. This does not seem
to make much sense. It is probably better to leave those fields
untouched.
Update ovs-vswitchd.conf.db(5) to match the change in implementation.
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Optimizing ovsdb_jsonrpc_mintor_flush_all() by avoiding calling
ovsdb_monitor_get_update() on monitors that do not have any
unflushed updates. This change saves CPU cycles on ovsdb-server's
main loop, but should not introduce any client visible changes.
Reported-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Liran Schour <lirans@il.ibm.com>
Acked-by: Ben Pfaff <blp@ovn.org>
This patch removes limits on number of concurrent sessions
allowed by ovsdb-server. Historically, it was not an design
goal for OVSDB server to support very high number of sessions.
The imposed limit reflects those design choices.
Work is now underway to improve OVSDB scalability since supporting
large of number of sessions is important for OVN, Removing
this limit makes scalability testing possible.
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Han Zhou <zhouhan@gmail.com>
Acked-by: Ben Pfaff <blp@ovn.org>
Commit 4c2809787cdbc774 (ovsdb-monitor: add json cache) introduced
an optimization that allows jsonrpc session to share monitors.
However, the memory/show implementation was not updated to match the
implementation; it still assumes that each jsonrpc session uses its
own monitor, thus are likely to over reporting the number.
This patch fix the bug and reports the actual number of monitor used
by the ovsdb-server.
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>
Without "void", this is a pre-ANSI style function definition that has
subtly different semantics.
Found by sparse.
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Andy Zhou <azhou@ovn.org>
Add test to make sure ovs-vswitchd fall back to use the
"monitor" method when connecting to an older ovsdb-server that
does not support "monitor2".
For testing backward compatibility, add an ovs-appctl command:
"ovsdb-server/disable-monitor2". This command will restart
all currently open jsonrpc connections, but without support for
'monitor2' JSON-RPC method for the new connections.
There is no corresponding enable command, since this feature is only
useful for testing. 'monitor2' will be available when ovsdb-server
restarts.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@ovn.org>
ovsdb-server now accepts the new "monitor2" request. The next
patch will switch IDL to use monitor2 by default.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@ovn.org>
Add functions that can generate "update2" notification for a
"monitor2" session. "monitor2" and "update2" are RFC 7047 extensions
described by ovsdb-server(1) manpage. See the manpage changes
for more details.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@ovn.org>
Although multiple jsonrpc monitors can share the same ovsdb monitor,
each change still needs to translated into json object from scratch.
This can be wasteful if multiple jsonrpc monitors are interested in the
same changes.
Json cache improves this by keeping an copy of json object generated
for transaction X to current transaction. When jsonrpc is interested
in a change, the cache is searched first, if an json object is found,
a copy of it is handed back, skipping the regeneration process.
Any commit to the monitor will empty the cache. This can be further
optimized to not throw away the cache if the updated tables and columns
are not being monitored.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
monitor
Store ovsdb monitor in a global hmap. If a newly created ovsdb monitor
object monitors the same tables and columns as an existing one, the
existing monitor will be reused.
With this patch, jsonrpc monitor and ovsdb monitor now have N:1 mapping.
The goals are to:
1) Reduce the cost of maintaining duplicated monitors.
2) Allow for create Json cache for the same updates. Json cache will be
introduced in the following patch.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
Currently, each monitor table contains a single hmap 'changes' to
track updates. This patch introduces a new data structure
'ovsdb_monitor_changes' that stores the updates 'rows' tagged by
its first commit transaction id. Each 'ovsdb_monitor_changes' is
refenece counted allowing multiple jsonrpc_monitors to share them.
The next patch will allow each ovsdb monitor table to store a list
of 'ovsdb_monitor_changes'. This patch stores only one, same as
before.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
jsonrpc_monitor_compose_update() seems to fit better than
jsonrpc_monitor_compose_table_update(), since it composes changes
from all tables. Albeit the original one is named after the
<table-updates> object described in RFC 7047.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
With N:1 mappings, multiple jsonrpc server may be servicing the rpc
connection at a different pace. ovsdb-monitor thus needs to maintain
different change sets, depends on connection speed of each rpc
connections. Connections servicing at the same speed can share the
same change set.
Transaction ID is an concept added to describe the change set. One
possible view of the database state is a sequence of changes, more
precisely, commits be applied to it in order, starting from an
initial state, with commit 0. The logic can also be applied to the
jsonrpc monitor; each change it pushes corresponds to commits between
two transaction IDs.
This patch introduces transaction IDs. For ovsdb-monitor, it maintains
n_transactions, starting from 0. Each commit add 1 to the number.
Jsonrpc maintains and 'unflushed' transaction number, corresponding to
the next commit the remote has not seen. jsonrpc's job is simply to
notice there are changes in the ovsdb-monitor that it is interested in,
i.e. 'n_transactions' >= 'unflushed', get the changes in json format,
and push them to the remote site.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
Currently, each ovsdb-monitor points to a single jsonrpc_monitor object.
This means there is 1:1 relationship between them.
In case multiple jsonrpc-monitors need to monitor the same tables and
the columns within them, then can share a single ovsdb-monitor, so the
updates only needs to be maintained once.
This patch, with a few following patches, will allow for N:1 mapping
between jsonrpc-monitor and ovsdb-monitor.
Maintaining jsonrpc-monitor pointers in a linked-list is essential
in allowing N:1 mapping. The ovsdb-monitor life cycle
is now reference counted. An empty list means zero references.
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
