Nir Soffer has posted comments on this change.

Change subject: utils: Add changehash function for change detection
......................................................................


Patch Set 4:

(1 comment)

https://gerrit.ovirt.org/#/c/33045/4/lib/vdsm/utils.py
File lib/vdsm/utils.py:

Line 1231:     h = hashlib.sha1()
Line 1232:     for s in strings:
Line 1233:         h.update(s)
Line 1234:     # Engine stores this in varchar(30)
Line 1235:     return h.hexdigest()[:30]
> How likely are we to experience a hash collision since we're taking only th
This break compatibility with old engines. I think we are safe, currently we 
are using 64 bit value, with this patch we are using 120 bit value.

If we want more bits, we can use base64 encoding:

    >>> base64.b64encode(h.digest())
    'C+7Hteo/D9vJXQ3UfzxbwnXaijM='
    >>> len(base64.b64encode(h.digest()))
    28


-- 
To view, visit https://gerrit.ovirt.org/33045
To unsubscribe, visit https://gerrit.ovirt.org/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: I2242a594383e2d2fe64e3a581f18b8ac662648b0
Gerrit-PatchSet: 4
Gerrit-Project: vdsm
Gerrit-Branch: master
Gerrit-Owner: Nir Soffer <[email protected]>
Gerrit-Reviewer: Adam Litke <[email protected]>
Gerrit-Reviewer: Allon Mureinik <[email protected]>
Gerrit-Reviewer: Dan Kenigsberg <[email protected]>
Gerrit-Reviewer: Federico Simoncelli <[email protected]>
Gerrit-Reviewer: Francesco Romani <[email protected]>
Gerrit-Reviewer: Jenkins CI
Gerrit-Reviewer: Jenkins CI RO
Gerrit-Reviewer: Nir Soffer <[email protected]>
Gerrit-Reviewer: Roy Golan <[email protected]>
Gerrit-Reviewer: Vinzenz Feenstra <[email protected]>
Gerrit-Reviewer: gerrit-hooks <[email protected]>
Gerrit-HasComments: Yes
_______________________________________________
vdsm-patches mailing list
[email protected]
https://lists.fedorahosted.org/mailman/listinfo/vdsm-patches

Reply via email to