On December 13, 2018 1:47:44 AM GMT+08:00, Quanah Gibson-Mount <quanah@sym= as=2Ecom> wrote:

Hi,

Thanks for the report! I have some questions:

a) Did you test with writemap enabled for mdb?

No, but I did test the unpatched slapd with writemap=2E it was not much fa= ster=2E I can test the patch with writemap to see what happens=2E

b) Did you test the effect on other operating systems? (I=2Ee=2E, Windows=

,=20

Solaris, FreeBSD, etc)?

No , I dont have any=2E The only thing I have is a x86-64 pc with linux=2E= I did try to avoid touching any os specific codes

c) Did you test multiple filesystems under Linux(I=2Ee=2E, ext2, ext3, ext4,=20 xfs, etc)?

no=2E I only tested with ext4=2E

d) What filesystem did you use when testing? Was journaling enabled or

disabled? What was the default flush behavior of the filesystem you used?

I used nobarrier, data=3Dwriteback mount options, which are faster than th= e default, but not significantly=2E I am using a very fast SSD though=2E

I=2Ee=2E, if you set dbnosync at the mdb level, the underlying filesystem flush=20 behavior will then be in effect (with ext4, for example, this defaults to 5=20 seconds)

something like that=2E it also depends on vm setting, like dirty ratio=2E

e) Did you test when the database is also writing to an underlying=20 accesslog database that is also backed by mdb?

no, I dont konw how=2E

--=20 Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E