Directory Tree - Generates a list of subdirectories.

[Tech99]

One scenario with FindFirstFileEx API which needs to measure, came to my mind. Enabling FIND_FIRST_EX_LARGE_FETCH flag and trying with search pattern '*'. Performance could be even better, if that kind of call would automatically recurse subfolders.

hFindFile = FindFirstFileEx(FolderPath & "\" & Pattern, FINDEX_INFO_LEVELS.FindExInfoBasic, m_WFD, FINDEX_SEARCH_OPS.FindExSearchLimitToDirectories, 0&, FIND_FIRST_EX_LARGE_FETCH)

Edit, tested performance, bit mixed results. Windows 7 workstation benefited enabling FIND_FIRST_EX_LARGE_FETCH flag and setting pattern to '*'. Server search did not, actually it was bit slower than querying without large fetch flag.

W7 workstation, 1285 folders
pattern *.* -> 6.8731, 6.9714 and 6.8767 seconds.
Pattern * and Large_Fetch -> 5.3779, 5.4598, 5.5258 seconds.

W12K R2 server, 19459 folders
Pattern *.* -> 3.1201, 3.1146, 3.1199 seconds.
Pattern * and Large_Fetch -> 3.2430, 3.2397, 3.2519 seconds.

W12K R2 server, via share 17434 folders
Pattern *.* -> 26.1318, 26.5813, 26.5810 seconds.
Pattern * and Large_Fetch -> 24.6481, 24.5381, 24.5071 seconds.

Interesting that server machine performs lesser when FIND_FIRST_EX_LARGE_FETCH flag is enabled.

btw... adding 19459 folders to listbox took 9.5 seconds (mean).

Quite a suprise is that the SMB perfomance is so much lesser (cpu Xeon E5 2620 v3 with 12 cores, 40 Gb memory, 4 x gigabit network, Smart Array P440ar controller), tuning tips are welcome.

Increase AdditionalWorkerThreads or what to try/do?
https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx
https://redmondmag.com/articles/2014...-problems.aspx
https://technet.microsoft.com/en-us/.../jj134210.aspx