glusterfs.git/xlators/protocol/client/src/client-handshake.c, branch v3.5.3beta2

protocol/client: conn-id should be unique when lk-heal is off

2014-06-27T08:42:03+00:00

        Backport of http://review.gluster.org/6669

Problem:
It was observed that in some cases client disconnects
and re-connects before server xlator could detect that a
disconnect happened. So it still uses previous fdtable and ltable.
But it can so happen that in between disconnect and re-connect
an 'unlock' fop may fail because the fds are marked 'bad' in client
xlator upon disconnect. Due to this stale locks remain on the brick
which lead to hangs/self-heals not happening etc.

For the exact bug RCA please look at
https://bugzilla.redhat.com/show_bug.cgi?id=1049932#c0

Fix:
When lk-heal is not enabled make sure connection-id is different for
every setvolume. This will make sure that a previous connection's
resources are not re-used in server xlator.

BUG: 1113894
Change-Id: I5090f832730e4072c4b6b6758e64f757b911bd49
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/8187
Tested-by: Gluster Build System 
Reviewed-by: Niels de Vos

protocol/client: handle network disconnect/reconnect properly

2013-12-03T19:35:32+00:00

if client/server state versions match, we still need to notify
parent xlators of reconnection (CHILD_UP) because they were
notified of CHILD_DOWN at the time of disconnection.

Change-Id: I36c4bde6d8c3db9cb0c48eeb10663b56897c932e
BUG: 1037267
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6398
Tested-by: Gluster Build System 
Reviewed-by: Krishnan Parthasarathi

libglusterfs: Add monotonic clocking counter for timer thread

2013-10-15T07:14:57+00:00

gettimeofday() returns the current wall clock time and timezone.
Using these functions in order to measure the passage of time
(how long an operation took) therefore seems like a no-brainer.

This time suffer's from some limitations:

a. They have a low resolution: “High-performance” timing by
definition, requires clock resolutions into the microseconds
or better.

b. They can jump forwards and backwards in time: Computer
clocks all tick at slightly different rates, which causes
the time to drift. Most systems have NTP enabled which
periodically adjusts the system clock to keep them in sync
with “actual” time. The adjustment can cause the clock to
suddenly jump forward (artificially inflating your timing
numbers) or jump backwards (causing your timing calculations
to go negative or hugely positive). In such cases timer
thread could go into an infinite loop.

From 'man gettimeofday':
----------
..
..
The time returned by gettimeofday() is affected by discontinuous
jumps in the system time (e.g., if the system administrator manually
changes the system time).  If you need a monotonically increasing
clock, see clock_gettime(2).
..
..
----------

Rationale:

For calculating interval timing for Timer thread, all that’s
needed should be clock as a simple counter that increments
at a stable rate.

This is necessary to avoid the jumps which are caused by using
"wall time", this counter must be monotonic that can never
“tick” backwards, ever.

Change-Id: I701d31e71a85a73d21a6c5cd15583e7a5a645eeb
BUG: 1017993
Signed-off-by: Harshavardhana 
Reviewed-on: http://review.gluster.org/6070
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

protocol/client: Prevent excessive logging of client's "disconnect" messages.

2013-05-28T11:38:25+00:00

Problem: Currently when gluster volume start force is executed, client process
         will talk to glusterd to get the port of the brick. But if brick's path
         is not available it cannot return brick's port. So client process will
         keep connecting and disconnecting from glusterd for port-query which
         is ultimately responsible for execssive logging of disconnect messages.

Fix:     Message will be logged just once at INFO level after the first
         disconnect from glusterd. Afterwards "disconnect" messages will be
         logged in DEBUG mode.

Change-Id: I2b787f3820b5da45e090c562e5698fcfe24a02cd
BUG: 959969
Signed-off-by: Venkatesh Somyajulu 
Reviewed-on: http://review.gluster.org/4953
Reviewed-by: Amar Tumballi 
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

protocol/client: Avoid double free of frame

2013-02-05T06:11:51+00:00

When client_submit_request fails it calls cbk. The cleanups should
happen only in cbk. The code committed as part of
http://review.gluster.org/4357 violates this. Also found that
clnt_release_reopen_fd violates this as well.
This patch fixes these issue.

Change-Id: Ic02ba278724b03c65c00b686c39fd7846122618a
BUG: 821056
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4464
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

protocol/client: Periodically attempt reopens

2013-02-03T19:33:31+00:00

If the brick is taken down and the hard disk is replaced
and the brick is brought back up, the re-opens of the open-fds
will fail because the file is not present on the brick.
Re-opens are not attempted even if the files are re-created by
self-heal until the brick is brought down after the files are
re-created and brought back up. This is a problem with a VM-store
in a replica-setup.  Until the fd is re-opened the writes will
never happen on the brick where the hard-disk is replaced.
To handle this situation gracefully, client xlator is enhanced
to perform finodelk, fxattrop, writev, readv using anonymous fds
if the file is yet to be re-opened. If the fop succeeds then client
xlator attempts re-open.

Change-Id: I1cc6d1bbf8227cd996868ab2ed0a57fb05e00017
BUG: 821056
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4358
Tested-by: Gluster Build System 
Reviewed-by: Jeff Darcy

protocol/client: Add fdctx back to saved-list after reopen

2013-02-03T19:33:18+00:00

Change-Id: I01caa1b51570359e6e3ffe1ffb7279cbdb0b0c64
BUG: 821056
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4357
Tested-by: Gluster Build System 
Reviewed-by: Jeff Darcy

protocol/client: print a message regarding brick status in case of failure

2012-12-20T12:05:18+00:00

that way, it would help admins to look at the corresponding brick directly.

All credit goes to Amar.

Change-Id: I959df59111864cc0574945d827f8fe5f2d919491
BUG: 839021
Signed-off-by: Krutika Dhananjay 
Reviewed-on: http://review.gluster.org/4341
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

client-handshake: synchronize config.remote_port setting b/w

2012-10-11T23:35:52+00:00

rpc_clnt_reconnect and client_query_portmap_cbk

problem:
-------
Theoretically there is a possibility that we could complete
querying the remote brick's port number before rpc_transport_connect
can return. If rpc_clnt_reconnect happens to be the caller of
rpc_transport_connect and we've already got the remote brick's port
number by the time rpc_transport_connect returns, without synchronization,
rpc_clnt_connect resets config.remote_port to zero even before we have
attempted a connection with remote brick.

fix:
---
By making only poll thread do setting and resetting of
config.remote_port, we avoid the race-condition.

Change-Id: I51879ba1cac651a80ff5c9c070ec7fe1ceea9e05
BUG: 765051
Signed-off-by: Raghavendra G 
Reviewed-on: http://review.gluster.org/4044
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

protocol/client: quick-reconnect after portmap query

2012-09-26T04:14:42+00:00

Currently the disconnect after a portmap query is treated like an
ordinary disconnect and the reconnection attempt (in this case, to
the brick) is attempted only after 3 secs. This results in a delay
which is unnecessary.

Mark the disconnection happening because of a successful portmap
query as needing a 'quick reconnect' to avoid the delay for this
special case.

Change-Id: I43c8292ff0c30858d883ff3569a3761acbf2f5eb
BUG: 860220
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/3994
Tested-by: Gluster Build System 
Reviewed-by: Amar Tumballi