History log of /5.5.2/kv_engine/engines/ep/src/statwriter.h (Results 1 - 23 of 23)
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Revision tags: v7.0.2, v6.6.3, v7.0.1, v7.0.0, v6.6.2, v6.5.2, v6.6.1, v6.0.5, v6.6.0, v6.5.1, v6.0.4, v6.5.0, v6.0.3, v5.5.4, v5.5.5, v5.5.6, v6.0.1, v5.5.3, v6.0.0, v5.1.3, v5.5.2, v5.5.1, v5.1.2, v5.1.1
# f789fb42 12-Apr-2018 Daniel Owen <owend@couchbase.com>

Add eviction category of stats

To aid with debugging potential performance issues a new category of
eviction stats is created.

In this category we maintain a histogram to record

Add eviction category of stats

To aid with debugging potential performance issues a new category of
eviction stats is created.

In this category we maintain a histogram to record the execution
frequency of items evicted from the hash table (a separate histogram is
used for active/pending vbuckets and replica vbuckets.)

We also maintain a snapshot of the last contents of the frequency
histogram (again, a separate histogram is maintained for active/pending
vbuckets and replica vbuckets.)

The stats can be retrieved using cbstats. e.g.

./cbstats default:11210 -u xxx -p xxx eviction

The "evicted" histogram stats provide an aggregated view of what the
execution frequencies are for all the items that evicted when running
the hifi_mfu algorithm.

The "snapshot" histogram stats provide a view of what the contents of
the frequency histogram is like during the running of the hifi_mfu
algorithm.

Example output:

ep_active_or_pending_eviction_values_evicted (102362 total)
0 - 0 : ( 3.78%) 3865 █▊
1 - 1 : ( 12.99%) 9436 ████▌
2 - 2 : ( 29.52%) 16913 ████████
3 - 3 : ( 50.85%) 21832 ██████████▍
4 - 4 : ( 97.23%) 47477 ██████████████████████▋
5 - 5 : ( 99.77%) 2602 █▏
6 - 6 : ( 99.96%) 199
7 - 7 : (100.00%) 34
8 - 8 : (100.00%) 3
10 - 10 : (100.00%) 1
Avg : ( 3)
ep_active_or_pending_eviction_values_snapshot (40 total)
2 - 2 : ( 2.50%) 1 █▎
3 - 3 : ( 22.50%) 8 ██████████
4 - 4 : ( 47.50%) 10 ████████████▌
5 - 5 : ( 65.00%) 7 ████████▊
6 - 6 : ( 72.50%) 3 ███▊
255 - 255 : (100.00%) 11 █████████████▊
Avg : ( 73)
ep_replica_eviction_values_evicted (68829 total)
0 - 0 : ( 1.37%) 945 ▋
1 - 1 : ( 2.01%) 441 ▎
2 - 2 : ( 2.92%) 621 ▍
3 - 3 : ( 6.39%) 2392 █▊
4 - 4 : (100.00%) 64430 ███████████████████████████████████████████████▋
Avg : ( 3)
ep_replica_eviction_values_snapshot (36 total)
4 - 4 : ( 25.00%) 9 ████████████▌
255 - 255 : (100.00%) 27 █████████████████████████████████████▌
Avg : ( 192)

Change-Id: I989efa9624cbbc9aa354c8cefbfef44be4ed258d
Reviewed-on: http://review.couchbase.org/92904
Tested-by: Build Bot <build@couchbase.com>
Reviewed-by: Tim Bradgate <tim.bradgate@couchbase.com>
Reviewed-by: Jim Walker <jim@couchbase.com>

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Revision tags: v5.0.1
# 8b25bbfd 24-Oct-2017 Eugen-Alexandru Virtan <eugen.virtan@couchbase.com>

MB-26047:[7-a] Change all stats histograms to use <chrono> durations

Part of a cross repo change.

Replace Histogram<hrtime_t> with MicrosecondHistogram and refactor
realted code

MB-26047:[7-a] Change all stats histograms to use <chrono> durations

Part of a cross repo change.

Replace Histogram<hrtime_t> with MicrosecondHistogram and refactor
realted code to work with durations.
Change various add_stat methods to accomodate the new changes to
templates introduced in histogram.h by the new patch in platform.

Change-Id: Ic061e11a79b09663b980e173dc4191d46d5aa35d
Reviewed-on: http://review.couchbase.org/84743
Reviewed-by: Dave Rigby <daver@couchbase.com>
Tested-by: Dave Rigby <daver@couchbase.com>

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Revision tags: v5.1.0
# 20d29ea3 10-Oct-2017 Dave Rigby <daver@couchbase.com>

Replace ProcessDurationHistogram with MicrosecondHistogram

Replace type alias 'ProcessDurationHistogram' with a more type-safe
MicrosecondHistogram. The new class uses std::chrono::micro

Replace ProcessDurationHistogram with MicrosecondHistogram

Replace type alias 'ProcessDurationHistogram' with a more type-safe
MicrosecondHistogram. The new class uses std::chrono::microseconds
internally, which (1) explicitly notes the unit that our histograms
actually end up recording and (2) is type-safe; any attempts to add
times in other units will have the correct automatic conversion
applied.

Change-Id: I764c803cc59758d307b752b85a923d1c1868034b
Reviewed-on: http://review.couchbase.org/84223
Reviewed-by: Manu Dhundi <manu@couchbase.com>
Tested-by: Build Bot <build@couchbase.com>

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Revision tags: v5.0.0
# 9f5e3d4d 24-Aug-2017 Dave Rigby <daver@couchbase.com>

Remove STATWRITER_NAMESPACE namespacing

Prior to C++11 we had to jump through some hoops to allow multiple
(identical) declarations of the same template name. This is no longer
neces

Remove STATWRITER_NAMESPACE namespacing

Prior to C++11 we had to jump through some hoops to allow multiple
(identical) declarations of the same template name. This is no longer
necessary, so simplify the code to remove these extra defines /
namespacing.

Change-Id: I6bd5e4cee97fafb327c1f357d629bbd28ffb96f5
Reviewed-on: http://review.couchbase.org/82694
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Build Bot <build@couchbase.com>

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# b298b60f 15-Aug-2017 Dave Rigby <daver@couchbase.com>

Histogram stats: Don't omit empty bins with printing

When printing Histogram objects as stats (for display via cbstats),
don't omit histograms bins which contain zero samples.

W

Histogram stats: Don't omit empty bins with printing

When printing Histogram objects as stats (for display via cbstats),
don't omit histograms bins which contain zero samples.

While it initially seems sensible to ignore empty bins, when printing
histograms from such data it can be difficult to get a representative
view of the underlying distribution if empty bins are not printed in
the middle of a range.

For example, consider the following histogram which is from before
this patch:

rw_0:snapshot (1296 total)
2us - 4us : ( 0.08%) 1
4us - 8us : ( 3.32%) 42 █▎
8us - 16us : ( 57.18%) 698 ██████████████████████▌
16us - 32us : ( 78.55%) 277 ████████▉
32us - 64us : ( 80.25%) 22 ▋
1ms - 2ms : ( 89.20%) 116 ███▊
2ms - 4ms : (100.00%) 140 ████▌
Avg : ( 321us)

Note this is a bimodal distribution, with peaks at 8-16us and
2-4ms. However, from looking at the cbstats rendering of this it's not
obvious that there's actually a significant distance between the two
peak - approximately 3ms.

If we include empty (zero count) bins, we get a very different impression:
view:

rw_0:snapshot (1296 total)
2us - 4us : ( 0.08%) 1
4us - 8us : ( 3.32%) 42 █▎
8us - 16us : ( 57.18%) 698 ██████████████████████▌
16us - 32us : ( 78.55%) 277 ████████▉
32us - 64us : ( 80.25%) 22 ▋
64us - 128us : ( 80.25%) 0
128us - 256us : ( 80.25%) 0
256us - 512us : ( 80.25%) 0
512us - 1ms : ( 80.25%) 0
1ms - 2ms : ( 89.20%) 116 ███▊
2ms - 4ms : (100.00%) 140 ████▌
Avg : ( 321us)

Here the two discrete peaks are much clearer - we get an actual
quantatative representation of the data.

Implementation note: This increases the set of statistics seen by
ep_testsuite tests which verify that (a) all expected stats are output
and (b) no extra, unexpected stats are printed. Thus far we have
implemented these tests using an explicit whitelist of expected stat
names. However, with this change we now emit a much larger set of stat
names for each of the zero-count histogram buckets - e.g.

rw_3:readSize_1048576,2097152
rw_3:readSize_128,256
rw_3:readSize_131072,262144

To avoid having to hardcode a large list of these kinds of stats -
whose keys will change if we adjust the histogram binning - this patch
adds support for specifying stat names using a regex pattern.

Given that these regexes cannot guard against extra stats being added
which happen to match the regex, this is only intended for
internal/auto-generated stat names which are *not* expected to be
exposed to end-users directly - we still want to maintain an explicit
set of user-visible stats.

Additionally, now that the full set of Histogram start/end ranges are
actually being emitted, ep_test_apis needs to be updated to handles
values up to uint64_t.

Change-Id: If2e9e420460fa185aff6c8e021800975d470b1d7
Reviewed-on: http://review.couchbase.org/82405
Reviewed-by: Oliver Downard <oliver.downard@couchbase.com>
Reviewed-by: Will Gardner <willg@rdner.io>
Tested-by: Build Bot <build@couchbase.com>

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# ef22f9b0 25-May-2017 Dave Rigby <daver@couchbase.com>

Move ep-engine to engines/ep


Revision tags: v4.6.2_ep
# d26ea7d1 20-Mar-2017 Dave Rigby <daver@couchbase.com>

Change GlobalTask::getDescription to return cb::const_char_buffer

The pure virtual method GlobalTask::getDescription() returns a
std::string object. This method is actually called very f

Change GlobalTask::getDescription to return cb::const_char_buffer

The pure virtual method GlobalTask::getDescription() returns a
std::string object. This method is actually called very frequently by
the ExecutorThreads (to log task execution / slow tasks), and hence
passing a concrete object is potentially costly, requiring an
allocation (and then deletion) for each call.

Given that the description is mostly constant for the lifetime of a
Task, change the method to return cb::const_char_buffer - i.e. a
read-only non-owning view. This reduces to passing essentially two
words, removing all memory allocation.

Change-Id: I3cd68798d97401a3d5b50c9720c87dade2a1b32e
Reviewed-on: http://review.couchbase.org/75435
Reviewed-by: Jim Walker <jim@couchbase.com>
Tested-by: Build Bot <build@couchbase.com>

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Revision tags: v4.6.2_mc, v4.6.1_ep
# 5b1d5b72 17-Jan-2017 olivermd <oliver.downard@couchbase.com>

MB-22181: Refactor Histogram to use smart pointers

As MB-22181 on platform changes the public API of Histogram, here the
uses of the API are updated to be consistent with the refactored

MB-22181: Refactor Histogram to use smart pointers

As MB-22181 on platform changes the public API of Histogram, here the
uses of the API are updated to be consistent with the refactored
Histogram

Change-Id: I75cdefc6d988e9f5c9f8b11345748e4959a8af58
Reviewed-on: http://review.couchbase.org/72116
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Daniel Owen <owend@couchbase.com>
Reviewed-by: Dave Rigby <daver@couchbase.com>

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Revision tags: v4.6.0_ep, v4.5.1-MP1_mc, v4.6.0-DP_mc, v4.6.0-DP_ep, v4.5.1-MP1_ep, v4.1.2-MP2_mc, v4.5.1_mc, v4.6.0_mc, v4.1.2-MP1_ep, v3.1.6_ep, v4.5.0_mc, v4.5.0_ep, v4.1.1_ep, v3.1.5_ep, v4.1.1_mc
# 66bb41ad 04-Mar-2016 Dave Rigby <daver@couchbase.com>

Remove AtomicValue and Mutex defines

We already removed our own custom AtomicValue and Mutex classes when
we moved to C++11; replacing them with #defines to std::atomic and
std::mute

Remove AtomicValue and Mutex defines

We already removed our own custom AtomicValue and Mutex classes when
we moved to C++11; replacing them with #defines to std::atomic and
std::mutex respectively. This patch completes that changover, using
the underlying types directly so it's easier to see what is actually
being used.

Change-Id: If3f717f766727042cd81ae7b8c65f9a19934f2fa
Reviewed-on: http://review.couchbase.org/60925
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Reviewed-by: Will Gardner <will.gardner@couchbase.com>

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Revision tags: v3.1.4_ep, v3.1.4_mc
# b84d09de 09-Feb-2016 Dave Rigby <daver@couchbase.com>

MB-17766: Regression test that checks for race during takeover

Module test: ep-engine_stream_test

Change-Id: I8e11722b1ed1029c8b969dcb88000c5903fbb0ca
Reviewed-on: http://review

MB-17766: Regression test that checks for race during takeover

Module test: ep-engine_stream_test

Change-Id: I8e11722b1ed1029c8b969dcb88000c5903fbb0ca
Reviewed-on: http://review.couchbase.org/59666
Well-Formed: buildbot <build@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: buildbot <build@couchbase.com>

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Revision tags: v3.1.5_mc
# 7e093e43 07-Dec-2015 Dave Rigby <daver@couchbase.com>

MB-16984: Use Histogram/BlockTimer from platform

ep-engine has a histo.h file which contains code to measure the
duration of code blocks, and to record that information into a
histog

MB-16984: Use Histogram/BlockTimer from platform

ep-engine has a histo.h file which contains code to measure the
duration of code blocks, and to record that information into a
histogram. To allow this code to be used by other projects it has been
moved into platform.

Update ep-engine to use the new, common version in platform and remove
ep-engine's own copy.

Change-Id: Idcb02d40167b2854422afdbdb80b13c3c4e266eb
Reviewed-on: http://review.couchbase.org/57589
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>

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Revision tags: v3.1.3_ep, v4.1.0_ep
# e7754280 05-Nov-2015 Dave Rigby <daver@couchbase.com>

Simplify common.h: Remove unnecessary headers [3/3]

Remove all #includes which arn't actually needed by the file including
them (aka "include what you use").

Reduces build time

Simplify common.h: Remove unnecessary headers [3/3]

Remove all #includes which arn't actually needed by the file including
them (aka "include what you use").

Reduces build time down from before this patch series from:

31.82 real 222.13 user 16.09 sys

down to:

26.95 real 188.54 user 13.29 sys

giving a 15% speedup in (user+sys).

(Built using `make clean && CCACHE_DISABLE=1 time make -j8`)

Change-Id: Ia47f08487d20c94167d93de8dd6590f7703dd898
Reviewed-on: http://review.couchbase.org/56705
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Manu Dhundi <manu@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>

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Revision tags: v3.1.2_ep, v4.1.0_mc, v3.1.2_mc, v3.1.1_mc, v3.1.1_ep, v4.0.0_ep, v4.0.0_mc, v3.1.0_ep, v3.1.0_mc, v3.1.6_mc
# 1e39e006 16-Apr-2015 Dave Rigby <daver@couchbase.com>

MB-14548: Print bool stats as 'true'/'false', not '1'/'0'

Also remove some duplicated / unnecessary printing of configuration
'stats' - these are already all printed by Configuration::ad

MB-14548: Print bool stats as 'true'/'false', not '1'/'0'

Also remove some duplicated / unnecessary printing of configuration
'stats' - these are already all printed by Configuration::addStats().

Change-Id: I7dfab4995b9a92e0e734d1d0d52caf1f672d82e5
Reviewed-on: http://review.couchbase.org/49850
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>

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Revision tags: v3.0.2-MP2_mc, v3.0.2_ep, v3.0.2_mc, v3.0.1_mc, v3.0.0_ep, v3.0.0-beta3_mc, v3.0.0_mc, v3.0.0-beta2_mc, v3.0.0-beta1_mc, v2.5.1_ep, v2.5.1-MP1-A_mc, v2.5.0_mc
# 9d8a9725 23-Dec-2013 Trond Norbye <trond.norbye@gmail.com>

Move towards using C++11 atomics

Start by renamimg all use of Atomics that doesn't "break" by
switching to std::atomic to AtomicValue (when the transition
is done we'll rename everyt

Move towards using C++11 atomics

Start by renamimg all use of Atomics that doesn't "break" by
switching to std::atomic to AtomicValue (when the transition
is done we'll rename everything back).

Change-Id: I3f694856dab498c565806c9ac1ee5baf3bc07b17
Reviewed-on: http://review.couchbase.org/31333
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: Chiyoung Seo <chiyoung@couchbase.com>

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Revision tags: v2.5.0-dp1_mc
# 7c6809d2 07-Nov-2013 Trond Norbye <trond.norbye@gmail.com>

Start migrate the API for our Atomics to look like std::atomic

This patch change the Atomic class CouchbaseAtomic, and change
the API so that:
get() => load()
set() => store(

Start migrate the API for our Atomics to look like std::atomic

This patch change the Atomic class CouchbaseAtomic, and change
the API so that:
get() => load()
set() => store()
cas() => compare_exchange_strong()

and move some of methods that used to be members as
template functions.

Change-Id: I48d873fbf04f40d446444232db44f565ee4fed54
Reviewed-on: http://review.couchbase.org/30135
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: Chiyoung Seo <chiyoung@couchbase.com>

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Revision tags: v2.2.0_mc, 2.1.1r_ep, 2.1.0r_ep, 2.0.2r_ep, 2.0.2r_mc, 2.0.1-macosx_ep, 2.0.1-linux_ep
# 66eb94d0 17-Jan-2013 Mike Wiederhold <mike@couchbase.com>

MB-7728: Add copyright headers to all files

This is something that our cpplint tool turns on and it makes
our product look a little bit more profesional. I have also
enabled the tool

MB-7728: Add copyright headers to all files

This is something that our cpplint tool turns on and it makes
our product look a little bit more profesional. I have also
enabled the tool to begin checking for these headers so it will
start complaining if we add a new file without a copyright header.

Change-Id: Ie956fdf7027bf56d9665ee455acd3c109fcacc76
Reviewed-on: http://review.couchbase.org/24560
Reviewed-by: Chiyoung Seo <chiyoung.seo@gmail.com>
Reviewed-by: Jin Lim <jin@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>

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Revision tags: 2.0.1-linux_mc, 2.0.0-couchbase_ep
# 244c0146 26-Nov-2012 Mike Wiederhold <mike@couchbase.com>

MB-7461: Alphabetize includes to conform with c++ standards

Change-Id: I71333dedada6530713b90184857bab9ac49d13df
Reviewed-on: http://review.couchbase.org/23515
Reviewed-by: Jin Lim <

MB-7461: Alphabetize includes to conform with c++ standards

Change-Id: I71333dedada6530713b90184857bab9ac49d13df
Reviewed-on: http://review.couchbase.org/23515
Reviewed-by: Jin Lim <jin@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>

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# 8f48f64b 23-Nov-2012 Mike Wiederhold <mike@couchbase.com>

MB-7426: Fix all header defines to conform with cpplint

Change-Id: I8253b640bc49ee8a0fabbb39ece73c2efdb906d5
Reviewed-on: http://review.couchbase.org/23510
Reviewed-by: Michael Wiede

MB-7426: Fix all header defines to conform with cpplint

Change-Id: I8253b640bc49ee8a0fabbb39ece73c2efdb906d5
Reviewed-on: http://review.couchbase.org/23510
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>

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# fc9615cd 23-Nov-2012 Mike Wiederhold <mike@couchbase.com>

MB-7405: Make extension for all header files .h

Change-Id: I7badb1e71c038b6498296c2893ccdbd47c2f0f87
Reviewed-on: http://review.couchbase.org/23483
Reviewed-by: Michael Wiederhold <m

MB-7405: Make extension for all header files .h

Change-Id: I7badb1e71c038b6498296c2893ccdbd47c2f0f87
Reviewed-on: http://review.couchbase.org/23483
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>

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Revision tags: 2.0.1-macosx_mc, v2.0.0_mc, v2.0.0-beta_mc, 1.8.1-MB-5845_ep
# bf3b555b 15-Aug-2012 Mike Wiederhold <mike@couchbase.com>

MB-6141: Move ep-engine source files into src directory

Change-Id: I6068c3aa7bc92d45bce4dd3097079665d807ac75
Reviewed-on: http://review.couchbase.org/19664
Reviewed-by: Michael Wiede

MB-6141: Move ep-engine source files into src directory

Change-Id: I6068c3aa7bc92d45bce4dd3097079665d807ac75
Reviewed-on: http://review.couchbase.org/19664
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>

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Revision tags: 2.0.0r_ep, 1.8.1_ep, v1.8.1_mc
# 5ff0677d 11-Apr-2012 Chiyoung Seo <chiyoung.seo@gmail.com>

MB-5010 Reset the thread local data whenever leaving a bucket.

A thread local data is set to a bucket pointer when a given
thread enters into that bucket for supporting the memory
ac

MB-5010 Reset the thread local data whenever leaving a bucket.

A thread local data is set to a bucket pointer when a given
thread enters into that bucket for supporting the memory
accounting per bucket. This means that the thread local data
should be reset when the thread leaves from its bucket.

Conflicts:

ep_engine.cc

Change-Id: I02124045c4503bf5d860e1063ab4d0aa11fd43b1
Reviewed-on: http://review.couchbase.org/14773
Tested-by: Chiyoung Seo <chiyoung.seo@gmail.com>
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Reviewed-on: http://review.couchbase.org/14919

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Revision tags: 1.8-MB-4901_ep, v2.0.0-dp4_mc
# b1997994 17-Feb-2012 Aliaksey Kandratsenka <alk@tut.by>

declare base add_casted_stat overload as inline and unbreak build

gcc with our paranoid warning levels complains that add_casted_stat
function (not template) is not declared before being

declare base add_casted_stat overload as inline and unbreak build

gcc with our paranoid warning levels complains that add_casted_stat
function (not template) is not declared before being defined.

Which kind of makes sense as duplicating trivial 'proxy' function in
all compile units is not what we need. Inline fixes it.

Change-Id: I28cef250b68ef4b4c93c3ba271953b2bd5bcb83f
Reviewed-on: http://review.couchbase.org/13337
Tested-by: Dustin Sallings <dustin@spy.net>
Reviewed-by: Dustin Sallings <dustin@spy.net>

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Revision tags: 1.8-MB-4738_ep
# ff84b291 15-Feb-2012 Dustin Sallings <dustin@spy.net>

refactor: Moved stat writing template generator stuff into a header file.

This makes it easier to delegate stat writing down to other stat
containers.

However, this has a nasty

refactor: Moved stat writing template generator stuff into a header file.

This makes it easier to delegate stat writing down to other stat
containers.

However, this has a nasty side-effect of identical duplicate template
functions being generated in separate compilation units and then
making the linker angry when bringing them back together. I'm
generating them in different namespaces with a gross mix of templates
and cpp.

http://www.youtube.com/watch?v=ruhFmBrl4GM

Change-Id: I333ca02d42c78c50e71226aa82b73c99a12142b2
Reviewed-on: http://review.couchbase.org/13269
Tested-by: Chiyoung Seo <chiyoung.seo@gmail.com>
Reviewed-by: Chiyoung Seo <chiyoung.seo@gmail.com>

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