[mythtv-commits] Ticket #2552: livetv, SwitchToProgram(), resets readahead buffer size to 4000KB

[MythTV]

#2552: livetv, SwitchToProgram(), resets readahead buffer size to 4000KB
-----------------------+----------------------------------------------------
 Reporter:  jwestfall  |       Owner:  ijr    
     Type:  patch      |      Status:  new    
 Priority:  minor      |   Milestone:  unknown
Component:  mythtv     |     Version:  head   
 Severity:  medium     |  
-----------------------+----------------------------------------------------
 When livetv auto-switches to the next file it calls ringbuffer->OpenFile()
 which resets the size of the readahead buffer back to the default of
 4000KB.  This is causing a number of glitches, especially with HD content.

 {{{
 2006-10-08 13:46:08.327 detectInterlace(Detect Scan, Interlaced Scan,
 29.97, 1088) ->Interlaced Scan
 2006-10-08 13:46:08.327 AFD: Looking for decoder for MPEG2VIDEO
 2006-10-08 13:46:08.327 AFD: Opened codec 0xb096d00, id(MPEG2VIDEO)
 type(Video)
 2006-10-08 13:46:08.327 AFD: Stream #1, has id 0x2049 codec id AC3, type
 Audio, bitrate 384000 at 0x0xae68d10
 2006-10-08 13:46:08.327 AFD: Looking for decoder for AC3
 2006-10-08 13:46:08.328 AFD: Opened codec 0x8994dc0, id(AC3) type(Audio)
 2006-10-08 13:46:08.333 NVP: Waiting for prebuffer.. 3
 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
 2006-10-08 13:46:08.344
 RingBuf(myth://10.0.0.125:6543/1107_20061008134732.mpg):
 CalcReadAheadThresh(39195 KB)
                          -> threshhold(1691 KB) min read(32 KB) blk
 size(512 KB)

 ...
 2006-10-08 13:58:40.925 LiveTVChain(live-
 mythfrontend-2006-10-08T11:07:06): SwitchTo(7)
 2006-10-08 13:58:40.926 LiveTVChain(live-
 mythfrontend-2006-10-08T11:07:06): Entry at 7: '1107_20061008140000'
 2006-10-08 13:58:40.952 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1519KB) vfl(29) frh(9) ne:0
 2006-10-08 13:58:40.986 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1486KB) vfl(29) frh(9) ne:0
 2006-10-08 13:58:41.018 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1420KB) vfl(29) frh(8) ne:0
 2006-10-08 13:58:41.052 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1355KB) vfl(29) frh(8) ne:0
 2006-10-08 13:58:41.115 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1322KB) vfl(28) frh(8) ne:0
 2006-10-08 13:58:41.139 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1256KB) vfl(28) frh(7) ne:0
 2006-10-08 13:58:41.163 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(1158KB) vfl(28) frh(7) ne:0
 2006-10-08 13:58:41.217 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(994KB) vfl(28) frh(6) ne:0
 2006-10-08 13:58:41.249 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(929KB) vfl(28) frh(5) ne:0
 2006-10-08 13:58:41.279 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(863KB) vfl(28) frh(5) ne:0
 2006-10-08 13:58:41.321 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(830KB) vfl(28) frh(5) ne:0
 2006-10-08 13:58:41.350 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(798KB) vfl(28) frh(4) ne:0
 2006-10-08 13:58:41.378 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(798KB) vfl(28) frh(4) ne:0
 2006-10-08 13:58:41.418 NVP: IsReallyNearEnd() br(4899KB) fps(29)
 sz(732KB) vfl(28) frh(4) ne:1
 2006-10-08 13:58:41.418 SwitchToProgram(void)
 2006-10-08 13:58:41.449
 RingBuf(myth://10.0.0.125:6543/1107_20061008134732.mpg):
 OpenFile(myth://10.0.0.125:6543/1107_200
 61008140000.mpg, 10)
 2006-10-08 13:58:41.467
 RingBuf(myth://10.0.0.125:6543/1107_20061008140000.mpg):
 CalcReadAheadThresh(4000 KB)
                          -> threshhold(402 KB) min read(32 KB) blk size(64
 KB)

 }}}

-- 
Ticket URL: <http://svn.mythtv.org/trac/ticket/2552>
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