"IDS seems to have shutdown cleanly"

Informix 11.70,TC4DE on Windows Vista: This is the message that onclean displayed when I shutdown the ol_informix1170 instance. Does the "seems" imply that there's no guarantee that the instance shutdown properly?.. Are any exit codes returned to verify that in fact the server shutdown properly, once its offline? I have been unloading large MS-DOS SE4.10 tables into 1170, which I configured for data warehousing, in order to do some number crunching and noticed this message. Then I went back into 1170 to check if everything was copacetic and it "seemed" to be.

Onclean is used to clean up shared memory and any orphaned oninit processes after a crash. So, when it finds that there is nothing to clean up it simply tells you that the server "seems to have shutdown cleanly" rather than having crashed. "Seems to..." because it could have crashed and happened to have been able to clean up after itself on the way down, but it "seems to have shutdown cleanly". Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Mon, May 7, 2012 at 1:36 AM, FRANK J. COMPUTER <frank_in_pr@hotmail.com>wrote: > Informix 11.70,TC4DE on Windows Vista: > > This is the message that onclean displayed when I shutdown the > ol_informix1170 > instance. Does the "seems" imply that there's no guarantee that the > instance > shutdown properly?.. Are any exit codes returned to verify that in fact the > server shutdown properly, once its offline? > > I have been unloading large MS-DOS SE4.10 tables into 1170, which I > configured > for data warehousing, in order to do some number crunching and noticed this > message. Then I went back into 1170 to check if everything was copacetic > and > it "seemed" to be. > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --14dae9340c0171205d04bf6f8aaf

Hmm, so wouldn't a better message be "onclean didn't find any problem that needed cleaning"?.. the "seems" made me feel like IDS could not totally guarantee that any problems were detected!.. Let me ask you this: I know for a fact that if an SE server crashes, it has no way of detecting that it crashed or that the client processes are notified that it crashed so that they can run an exception routine to perhaps gracefully exit. Now if IDS 11.70 crashes, is it aware it crashed, log an alarm in an OS logfile, signal client processes, or provide an automated mechanism for repair and restarting the server? I recently changed RA_PAGES to 256, and RA_THRESHOLS to 128 in INFORMIXDIR\\\\etc\\\\onconfig.ol_informix1170 and when I tried to connect to it, with DBACCESS, it displayed "Running..." and froze up, forcing me to close the window. Now it wont connect anymore!

See below, inline: Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Mon, May 7, 2012 at 7:26 AM, FRANK J. COMPUTER <frank_in_pr@hotmail.com>wrote: > Hmm, so wouldn't a better message be "onclean didn't find any problem that > needed cleaning"?.. the "seems" made me feel like IDS could not totally > guarantee that any problems were detected!.. > That's a tomayto/tomahto issue really. > > Let me ask you this: I know for a fact that if an SE server crashes, it > has no > way of detecting that it crashed or that the client processes are notified > that it crashed so that they can run an exception routine to perhaps > gracefully exit. > That's because SE has no central server to crash. Each client is really running its own private copy of the server. > > Now if IDS 11.70 crashes, is it aware it crashed, log an alarm in an OS > logfile, signal client processes, or provide an automated mechanism for > repair > and restarting the server? > Yes, yes, and yes. The server not only knows that it is in the process of crashing, but it knows at the time you restart it that it had crashed and had not shut down normally. There are several mechanisms that make that happen. First, there are three virtual processors (oninit processes), the ADM VP, the MSC VP, and the first CPU VP that watch each other and the other virtual processors. If any of these three crash the others instigate an emergency shutdown to prevent disk corruption. If any of the other VPs crash they clean up locks and latches held by the crashed VP and start a new one to replace it. Second, when the engine is running its current run state is recorded on the 0th page of the root chunk. During a normal shutdown that state is updated to indicate a normal shutdown. If the server starts up and the recorded state is not <down> then the server knows that it may have to run through recovery. Third, during normal shutdown a hard checkpoint is performed which flushes the logical log buffers to disk, writes all dirty pages from the buffer cache to disk, and empties the physical log since it is no longer needed. If the server starts up and the current length of the physical log is not zero then again, it knows that it must perform a recovery which entails restoring the physical log pages to disk to get a clean slate as if the previous checkpoint to which it can apply the logical log records, then it rolls forward the logical log transaction records beginning at the last completed checkpoint up to the end of the logical logs and rolls back any incomplete transactions. Only then is the server state changed to <online> and the server made available to users. As far as alarming the crash event, there are two scripts, the ALARMPROGRAM and the SYSALARMPROGRAM, which are executed when certain events happen. When the server is crashing, depending on which VP detected the crash, one of these scripts will be executed with arguments indicating the event that caused the alarm to trigger. The contents of the scripts determines what happens then. If the SYSALARMPROGRAM is the one that triggered, by default it performs some memory and core dumps and some onstats that tech support can use later to diagnose a recurring problem. Normally the ALARMPROGRAM default code for most events is to do nothing unless you change the script that is run or modify the delivered default script. Obviously if the whole machine crashes, nothing is logged or noted. > > I recently changed RA_PAGES to 256, and RA_THRESHOLS to 128 in > INFORMIXDIR\\\\etc\\\\onconfig.ol_informix1170 and when I tried to connect to it, > with DBACCESS, it displayed "Running..." and froze up, forcing me to close > the > window. Now it wont connect anymore! > That is not because of the changes you made. Indeed RA_THRESHOLD is deprecated in 11.70 and is ignored and RA_PAGES is also deprecated, but still active. However it should no longer be used in favor of the new AUTO_READAHEAD parameter (RA_PAGES will override the pages setting of AUTO_READAHEAD if present and set). The readahead values you set are very high, and I don't tune them that way myself because most of the servers I deal with are reading from SANs which have lots of cache and do readahead and which have intelligent drive controllers which themselves have cache and perform readahead and which are managing SCSI or SATA/PATA drives which are intelligent and have on-board cache and do their own readahead. I simply don't see the purpose to wasting server cache on readahead when all that readahead data is available from downstream rather cheaply. Anyway, side issue, the main point is you didn't cause the problem with your tuning changes. What you have encountered is a know problem running on Windows, it never happens on Linux/Unix. On my laptop (WinXP) I have two servers that used to start up on boot up. At some point, for no reason I have ever determined, they stopped accepting connections, though they would start up and shutdown normally every time. I have reinstalled and even upgraded the instance's versions to no avail. I no longer start them at all. I have my Linux engine on my home desktop and I have Linux VMs running Innovator Edition and Developer Edition on the laptop that I can start up when I need access to an Informix instance, so I have not pursued the problem with support. I don't like Windows and just don't personally care if the problem gets solved frankly. On the other hand, you apparently have a vested interest in running Windows based servers, so I would suggest calling tech support and seeing what they have to say about it. > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --047d7b15a9036f808b04bf724cdc