Re: ALR Quad6 4 CPU and Informix RSAM Version 5.03.UC1 on SCO 3.2v4.2 hangs

Michael Huehne (Michael.Huehne@Germany.EU.Net) wrote: : Hi folks, : any help would be appreciated. A new customer of mine needs some : support from me. He is the owner of several ALR Quad6/QSMP4 : machines. The main configuration is shown below. I have never seen : the machines before. But I want ask you for some useful hints. Maybe : I do not need to reinvent the wheel again ? If you need more details : I am willing to deliver the missing informations. : The main application is a relational Informix Turbo RSAM Version : 5.03.UC1 SQL data base (I am not shure about the database version at : all). <Detailed problems snipped for brevity, related parts retained in explanations below> : While backing up the machine with the dedicated Adaptec 2940U : adaptor and the Sony DAT tape; again, sometimes the machine hangs. : Now my questions: : ================= : Have you ever heard about such a strange behaviour ? My first idea : would point me to a problem with the main RAM or the main ADAC : disk RAID controller includes 32 MB Cache. Although I haven't seen this exact behaviour (total system lockups, etc.) before, we did have no end of trouble with Informix Online 5.03 on SCO 3.2.4.2. We had Informix tech support working on the problem. Basically what appeared to be happening was that the messages the server sent to the client via InformixNet were getting corrupted on the way. This caused many strange side-effects, including "408" errors, and massive performance problems. We finally switched to Dynamic Server (7.10), and that solved our problems. This was about two years ago, so my memory may be a bit foggy. I could dig up some more details if necessary. A followup question. The problems you are experiencing with the backup procedure, is this an Informix archive (tbtape), or an OS backup using tar (or similar product)? If it's tbtape, how far does the backup get before the system locks, and what type of archive are you doing? Also, how are the database tablespaces laid out? Are you using raw disk partitions? : Have you every seen such an ALR computer in a similar : configuration working fast and solid like a rock as an Informix : database server ? We have used a _similar_, but not quite identical ALR, SCO and Informix with tremendous success. The difference is that we have been using the Mylex RAID controller, not the Adaptec (we purchased our first machines before ALR supplied the Adaptec, and since the Mylex worked, we stuck with it). We have gone 100+ days without any difficulty at all. : Have you any hints which parameters in the /etc/conf/cf.d/stune : file need to be modified for great performance with all 4 CPUs. If I were using 4 CPU's, I'd upgrade to Dynamic Server, which supports multiprocessing. : Have any thumb rules which other kernel parameters normally needs : to be modified for large Databases ? The release notes supplied with Informix are what I consult first, after that, just the normal performance tuning stuff. Most deal with shared memory, and possibly MAXUMEM if my memory serves me correctly. : Are there are any good performance monitor programs available for : the old SCO-Unix 3.2v4.x ? Whats the price in $ or DEM and what is : the name of the brand and which company is actually selling the : tool ? I just use "u386mon", "memhog" and the like, which are ftp-able from a variety of sites including "ftp.celestial.com". Several of the "super tar" backup companies also supply performance monitoring tools as well, I believe. I would have to agree with you that there appears to be something amiss in the HD subsystem (controller, bad cache, etc.) However, as I mentioned, the Adaptec controller is the one piece I can't be of help on. E-mail me if I can be of any help. -- ---------------------------------------------------------------------- Jim Bos E-mail: jbos@dordt.edu Director of Computing Services Dordt College Sioux Center, IA