We have an application that has three separate databases open  at the same time. It is currently always used in file-sharing as opposed to Client-Server mode.

For a few of our users, one of those databases may grow to a size that would require LargeFileSupport to be enabled.

I have two questions.

1) Is it possible to use LargeFileSupport for one database and not for others (eg through UseLocalSessionEngineSettings) and, anyway

2) What are the implications of using LargeFileSupport for databases where it's not necessarily needed? Is it purely the lower-level calls to the file system or does it affect other things - locking, concurrent access, indexing etc.. Will it affect performance?

I should also say I understand LargeFileSupport is only useable with versions of Windows that support NTFS but that isn't an issue for us. We also understand that all users concurrently accessing a single database must use the same setting for LargeFileSupport.

Thanks

Jeff
Jeff Gallant
Technical Manager
Computing for Labour
United Kingdom

Jeff

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1) Is it possible to use LargeFileSupport for one database and not for others (eg through UseLocalSessionEngineSettings) and, anyway
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LargeFileSupport is a property of engine and you can use it for one database only if there are two (or more) applications involved in the databases access. If you have just one application there is only one engine and therefore every access to ALL databases should be made using or not the setting except if you close the engine, change the setting and access other databases

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2) What are the implications of using LargeFileSupport for databases where it's not necessarily needed? Is it purely the lower-level calls to the file system or does it affect other things - locking, concurrent access, indexing etc.. Will it affect performance?
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None, Yes it is a pure low-level call to the file system and it does not affect the performance.

In my applications I have defined LargeFileSupport to "true". This way I can avoid mixing access to the same database throught many applications using different LargeFileSupport settings.

Eduardo (HPro)