Avoid trashing page cache on Tx.Copy().

This commit change the database copy to use O_DIRECT so that the Linux page
cache is not trashed during a backup. This is only available on Linux.

1 files changed, 2 insertions, 0 deletions

diff --git a/bolt_linux.go b/bolt_linux.go
index 351b65a..4351db5 100644
--- a/bolt_linux.go
+++ b/bolt_linux.go
@@ -5,6 +5,8 @@ import (
 	"syscall"
 )
 
+var odirect = syscall.O_DIRECT
+
 func fdatasync(f *os.File) error {
 	return syscall.Fdatasync(int(f.Fd()))
 }