This index is unused - we can gain some create performance by removing it.
To verify this, I ran createmany for 10 million files:
$ createmany -o '/scoutfs/file_%lu' 10000000
Before this patch:
total: 10000000 creates in 776.54 seconds: 12877.56 creates/second
real 12m56.557s
user 0m7.861s
sys 6m56.986s
After this patch:
total: 10000000 creates in 691.92 seconds: 14452.46 creates/second
real 11m31.936s
user 0m7.785s
sys 6m19.328s
So removing the index gained us about a minute and a half on the test or a
12% performance increase.
Signed-off-by: Mark Fasheh <mfasheh@versity.com>