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Justin, Does the decoder bin/decod_dcrast close its standard input stream? If so, what criteria does it use to make that decision? Does the same decoder terminate after completely reading a data-product on its standard input stream but before it reads an end-of-file on that stream? Regards, Steve Emmerson ------- Original Message Date: Mon, 14 Nov 2005 10:01:49 -0500 From: Justin Cooke <address@hidden>To: Steve Emmerson <steve@uni data.ucar.edu> cc: address@hidden, Paula Freeman <address@hidden> Subject: Re: hung downstream LDM Hi Steve, Steve Emmerson wrote: >>Well we are now at day 6 and the NEXRAD2 feed is still going! >> >>I'm not sure at what time mark we call this a success but it looks >>really good so far. >> >> > >You said previously that the time-to-failure ranged from 6 to 50 hours. >Six days is 144 hours, so I'm quite happy with the results. > > Well we are now at 12 days (288 hours) without any stoppage of the NEXRAD2 feed :). But we are seeing a few odd things in our ldmd.log, we are getting several "broken_pipe" errors which then cause a write error. I passed this along to our main decoder developer (Jeff Ator) and here is his response: --- Hmm, this is interesting, and it looks like it's something peculiar to this new LDM 6.4.3.0 that went in on 11/2/05, because these same "Broken_pipe" messages aren't showing up in the LDM log files prior to that date (i.e. ldmd.log.15, ldmd.log.16, ..., ldmd.log.20). What's really interesting is that these messages correspond exactly to when a decoder starts up, i.e. when a bulletin comes in for a particular decoder that isn't already running, and therefore pqact needs to start it up by forking a child process. In other words, the first bulletin that causes the new decoder process to start up is also the same one that is generating the "Broken_pipe" message in the logs, and it's happening for all of the decoders! Now this isn't a problem per-se, because these same bulletins are actually getting into the respective decoders, as I could confirm within the actual decoder logs themselves (perhaps this is due to the "pipe_prodput: trying again" completing successfully, as you pointed out below(?)). Either way, it's a bit unnerving, not to mention misleading, to suddenly be seeing all of these "Broken_pipe" messages, especially since they weren't occurring prior to the installation of the new LDM 6.4.3.0 build. ---- Here are a few of the log file entires: --- Nov 14 05:03:15 b2n1 pqact[434350] INFO: pipe: bin/decod_dcrast -v 2 -t 600 -d /dcomdev/us007003/decoder_logs/decod_dcrast.log /dcomdev/us007003/bufrtab.FSL_RAST /dcomdev/us007003/bufrtab.002 Nov 14 05:03:15 b2n1 pqact[434350] ERROR: pbuf_flush (27) write: Broken pipe Nov 14 05:03:15 b2n1 pqact[434350] ERROR: pipe_put: bin/decod_dcrast-v2-t600-d/dcomdev/us007003/decoder_logs/decod_dcrast.log/dcomd ev/us007003/bufrtab.FSL_RAST/dcomdev/us007003/bufrtab.002 write error Nov 14 05:03:15 b2n1 pqact[434350] ERROR: pipe_prodput: trying again ... Nov 14 05:13:42 b2n1 pqact[434350] INFO: pipe: bin/decod_dccgrd -v 2 -t 300 -d /dcomdev/us007003/decoder_logs/decod_dccgrd.log /dcomdev/us007003/bufrtab.001 tables/stns/cg.tbl Nov 14 05:13:42 b2n1 pqact[434350] ERROR: pbuf_flush (36) write: Broken pipe Nov 14 05:13:42 b2n1 pqact[434350] ERROR: pipe_put: bin/decod_dccgrd-v2-t300-d/dcomdev/us007003/decoder_logs/decod_dccgrd.log/dcomd ev/us007003/bufrtab.001tables/stns/cg.tbl write error Nov 14 05:13:42 b2n1 pqact[434350] ERROR: pipe_prodput: trying again --- I just stumbled on this when doing a grep for "error" in ldmd.log even though we've had no reported problems. Any ideas? Thanks again for all the attention you have given this, Justin ------- End of Original Message