Experiences of a FileMaker Pro Database Developer

Configuring FileMaker Server Cache

Fine tuning FileMaker Server cache can greatly improve performance in a large or heavily used solution. So, what is the optimal cache setting? I find that the general rule for setting cache is to set the RAM to the recommend setting that FileMaker Server suggests. I would leave the interval set at the default 1 minute, increasing the interval could leave you at a greater risk of loosing data.

Depending on what your solution is designed to do and how active the solution is, and whether you are writing or reading more data, you may be able to adjust the cache to tweak performance. Think of it this way, if you are writing more data by doing more edits or creating more records, then a smaller cache size may improve performance. Smaller chucks of data are written at a time. If you are reading more data, like running reports, then a larger cache size may improve performance since more data will be accessed from RAM instead of having to keep reading from disk.

In Windows Server 2003 or 2008, I recently confirmed that the memory usage on fmserver.exe is directly related to cache size. Whatever the cache is set to, that will be the minimum memory usage plus whatever extra ram is needed by FMS. The cache memory is reserved, regardless if it’s filled up or it’s empty. It kind of works like a RAM disk.

If you pop up Task Manager and click on the Processes tab and find fmserver.exe, watch the memory usage. Then go to the Admin Console, Configuration, Database Server, Databases and change the Cache size and click save. Watch the memory usage for fmserver.exe and you’ll see it change as you change the cache. There is need to restart FMS. Now you can tweak the cache setting until you find the optimum performance.

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  1. Hello,
    I’m working on a solution that is hosted in FMServer12 with almost 100 client connections at any given time (some are via web publishing) and I see about 20-30 clients get kicked off per day for warning: {Client “user name (computer name) [IP Address]” no longer responding; connection closed (#)} where # is usually 10 but sometimes 51. I’m wondering if tuning cache settings might help me with this problem because users report that they are kicked off during FM scripts that call pdf plugins and, I believe, demand RAM. All the users’ machines are 32-bit, 4 gigs of RAM.. Thanks for any advice.

  2. Matt… we seem to be having issues with VERY slow writes. Should I start by cutting our cache size in half, then increase?

    OR… should I drop it further?

    Thanks for your advice!

    • Hi Mike,

      Which version of FMS are you running? What makes you think writing is the bottleneck? Are you looking at the Disk KB/sec Written in the Server statistics? My post needs to be updated for FileMaker 13 which no longer has an interval option. Some specs on your server would be helpful too and if anything else is running with FileMaker Server. Plus, how many users and what size is your database system (records, gigabytes, etc). You can try cutting Cache in half and test, but I am thinking there might be other issues causing your slowness.

      Best Wishes,

      • Thank you so much for replying… I recently started a new job and inherited the system. I am really just now learning how FileMaker works, so please bare with me.

        We are running FileMaker Server 12 on a Windows 2008 server. We have roughly 36 users connected at the same time. We also have roughly 50 databases that support one large application. They combine to a total of 12 GB of space.

        It was setup as a VM on a HyperV setup. It has been given 16GB Ram and 4 Virtual CPUs. I know that running it on a VM is not ideal…

        Looking at the disk i/o, disc writes are going from 16 – 40+ ms. Reading is typically under 10 ms.

        Thanks again. I am going to figure this thing out eventually!!!

        • Hi Mike,
          VM is not ideal and the size of your system and number of users warrants a dedicated FileMaker Server box. I’m not sure what else is running on your machine. A lot of issues could be just in the design of the system. What exactly is the problem and what are the users experiencing? If it’s slowness and lag times, is this happening all the time or in specific areas? Are there server-side scripts and are these running or any other schedules running when things slow down? Are you using progressive backups and/or FileMaker backup schedules?
          I think you are in Georgia and work for New World Graphics. I’ll check and see if anyone I know is in your area, but it might be worthwhile to bring in a consultant for guidance and an onsite opinion. I’ll do the best I can to help. Is FileMaker running the entire business, from work orders to customer management and invoicing? Is any of this connected to the web?
          I know, a lot of questions. I’m familiar with your business as I started my career as a t-shirt designer for a company in Mississippi, designing apparel for colleges and universities. That was too long ago! I miss that industry.
          Best Wishes,

          • The main issue is that users have been having times where the system runs extremely slow. If more than one user is entering orders at a time, it basically crawls. I do not believe that there are progressive or FileMaker specific backups happening. I checked the Admin Console and there aren’t any scheduled.

            We do use this system to run our entire business and we don’t have it connected to web. It is strictly an internal network system.

            We are in Athens, GA!

            Thanks again for the help!!!

          • Hi Mike,
            You’re not too far from my brother who’s in Gainesville. I could never get him into FileMaker development though…

            Two things worry me with your response. The first is that there appears to be no backups in place. I highly recommend progressive backups and then hourly or every 2 hours backing up with a FileMaker schedule. It all depends what you can afford to loose if the system crashes. The second thing is you say it’s slow when entering data. This seems to be a structure problem with the design of the system. The question here is what is happening while doing data entry? Does it save as they tab through the fields, or is their a submit or commit record step when all done? Does it do any validation or checking along the way or at the end? Does it slow down more as you add more users entering orders?

            The system I am working on now is about 20GB in size and we have about 25 users. We are running FileMaker 13 for both Pro and Server, which does seem a bit faster than 12. This system runs on a dedicated Windows 2008 server with 32GB of RAM. about 16GB is dedicated to the Cache and I just checked and FileMaker Server is using a total of 21GB right now. The Raid subsystem and drive system is probably your most critical component. The C Drive is run on 15K SAS drives and RAID 10. This is where the FileMaker Server Application and supporting files reside. The Live databases are on a server-class SSD RAID card. All this is on a DELL R710. I’ve done a lot of testing and we have big data and progressive backups every 10 minutes with full databases backups every 2 hours. The users do not “feel” when any of this happens.

            A big factor in performance is design and how the user interacts and enters data. It could be one un-stored calculation that get’s updated as the user enters data that is causing the slowness. Something like a status field or “open orders” count field.

            I would highly recommend spending some time and money with a good consultant. This would help with your education and understanding and would save you a lot of time and aggregation. Chris Moyer with The Moyer Group who is in Decatur would be my first choice and recommendation. Chris is a fantastic guy and has been in the FileMaker community for many years.

            I could try and help you remotely, but my time is very limited since I no longer run my own business.

            Hope this helps,

  3. Here is a comprehensive guide to FileMaker Server Performance
    Cheers, Nick


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