Low performance

Since some time ago, my Navision 2.60 system is going slower. My server: 512 RAM, PIII 1 GHz., Windows NT 4.0 +SP6. Raid 1 with 2 logical drives. Arcserve 2000 and Navision Financials 2.60 for 12-14 users. I use this server as a print server + HP 2200 DN printer. This server acts as PDC as well. I am planning to disable this function and install the printer using the “peer to peer” method. I am using 2 switches (Ovislink). I am planning to buy a 3com 4400 48 ports to prioritize the network traffic. Do you know any technical document related to this topic? I mean Navision with network congestion… I tried to increase the Commit cache value, but no effect about the performance. I used a tool called Diskeeper 7.0 to analyze how fragmented the disks are. Disk 1: 2 partitions (C and D) Disk 2: partition E. Navision FDB files are stored in the D and E drive. The C drive is heavily fragmented. I will defrag it, sure! Does anyone have experience about defragment NT servers + Navision? Any suggestion?[8)]

How many files have you got? How many free space have you? Where are database files? Navision server or SQL Server dabase?


Originally posted by Agustin Carceller
How many files have you got? 4 files of 2 GB size. How many free space have you? Between 60-70 %. Where are database files? The database files are 2 in the D drive and 2 in the E drive. C drive is used for the Operating System. Navision server or SQL Server dabase? Navision server. No SQL. [:)]

To start with, you should add HD’s… should be 1 for each database file, plus the RAID disks, best would be SCSI drives, though I guess you have those. RAM should be fine, and use a separate machine for PDC as you plan to do. Just remember disks and disk speed are the most important issue with the native db. Saludos Nils

OK, I know the more disks I use the more performonce I will get upto 8 disks (RAID 1). I used a defragmentation tool, too. But I wonder if I can speed up the database if I click File, Database, Information. Click Tables, then select all tables. Click the Optimize button. My utilization is 78% so: Do you think if I use this procedure (Optimize) I will obtain more space available and I will improve the performance as well? [;)] Is it recommended by Navision or not? Thanks 4 your help!!!

If you have never used the Optimize table function, you should use this before you start spending money on Hardware upgrades. Not only will this reduce the space occupied by each table, it will also improve the way the data is stored in the tables. I see you have a total DB size of 8 GB. If you are running this configuration non-stop for some months, you will be amazed at how much free space you reclaim by Optimizing. Good luck

Also, instead of optimizing one table at a time, if you backup the entire database and then restore it to a new database file, you would optimize all tables, you could also make the new database size smaller this way. Navision does not store table keys data in the backup file, instead it will re-create your table keys when you do a restore after importing tables data. Doing table tests after restore is not necessary, as all created keys are correct. I used to do that from time to time, and do a full backup to another hard drive using Partition Magic.

Be aware though that Optimization will give you more available space, BUT it will NOT increase performance. (Unless of course you currently have less than 25% free space of course , but that is a different issue). In fact generally if you optimize disk space, you may find that performance actually drops. Shaman’s suggestion on the other hand, (if you can afford the luxury), is a good way to optimize without loosing performance.

This is quite similar to our installation and we had a few performance issues until we did a few things - - assuming you are also using InoculateIT ? - get the documentation from either the CAI or Microsoft Knowledge Base sites on how to exclude the Navision Service .EXE from virus scanning. You do not want the Virus scanner checking every database access. - set the server cache to a value between 256M and 384M on your machine with 512M - leave at least 128M for Windows - turn on commit cache - PLEASE use a UPS if you turn this on. - If you only have one physical (logical on a RAID controller) HDD DO NOT create multiple .FDB files ! 2 x .FDB files on one HDD ran about 3 times slower than 1 large .FDB file for us. With these simple changes we have no performance issues today.

More information: I copied my 4 FDB files to a hard disk and I optimized the most biggest tables (Iten Ledger Entry and Production Line Archive…) I realized I could save disk space, almost 600 MB (not too bad). I am using 2 companies: I could discover 2 tables used in the “Test Company” with more than 1.3 GB. My idea is to delete old records in both tables. [:D] So, do you think I could have better performance having 2 files of 4 GB files splitted in 2 hard drives instead of 4 files of 2 GB? But in I have found many times in this forum that the recommendation for files FDB is 2 GB… Kind regards,

Yes in my experience if you have 2 HDDs then 2 FDBs of 4G one per HDD will work better than 4 FDBs of 2G two per HDD. What I believe Navision would like is FDBs of 2G each on a separte HDD. In the days of 2G HDDs and small databases this would be fine. In the ‘Real World’ of today with 100G+ HDDs and 50G+ databases I don’t think so.

In rough terms(within 5%), 2 drives are twice as fast as one, 6 drives are six times as fast as one etc…

Getting the PDC and print services off the server should help. PDC’s can take up a lot of resources and RAM, especially, although in your shop, should not be too bad. Make sure that the 3com that you are considering purchasing is a switch. Switches handle the traffic much better than regular hubs. A OS level defragmenting tool should be kept away from the actual database files, but it should improve performance of the general operating system. Also, get the Pagefile defragmenter tool (pagedefrag) from www.sysinternals.com for maximum performance of the OS. Also, disable any services that you may not need anymore. Make sure you also disinclude the database files from the the virus scanning software as well.

Hi again, I discovered a better performance when I increased the Commitcache memory in the server from 64000 to 360000 KB. Now I can close production order entries (manufacturing module) in seconds instead of minutes. Maybe the key is the Commitcache!!! But I will know it in the next days… A great advance, anyway!!! But I would like to adjust this value properly. Does anyone know a rule to set it based on the database size? I set the DBMS value in the server to 360000 KB (Database size= 8000000 KB). So far, [:D]

Navision rule: 20Mb per 1Gb database 8Mb per session (average user) example: database 4 gb with 10 users = 4x20 + 8x10 = 160Mb cache

Hi, I had to expand the commit cache upto 360000 Mb and I expanded 1 GB my DB (9000000 KB in total). Now it is working pretty fast. So there is a strong relation between Database size and Commit cache size. From my point of view, this topic is shorted!!! Thank you for all your advices!!!