tahoe-lafs/trac-2024-07-25

S3 backend: either handle or avoid truncated get_bucket responses #1678

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opened 2012-02-16 18:04:45 +00:00 by davidsarah · 14 comments

davidsarah commented

2012-02-16 18:04:45 +00:00

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The GET Bucket AWS call may return a truncated response, by default after 1000 objects (doc). Currently we don't take that into account (actually I forgot that we didn't :-( ), which might be causing some of the 410 Gone errors.

In the meantime, here is a patch to log this case as WEIRD, so that it will trigger an incident.

The GET Bucket AWS call may return a truncated response, by default after 1000 objects [(doc)](http://docs.amazonwebservices.com/AmazonS3/latest/API/RESTBucketGET.html). Currently we don't take that into account (actually I forgot that we didn't :-( ), which might be causing some of the 410 Gone errors. In the meantime, here is a patch to log this case as WEIRD, so that it will trigger an incident.

tahoe-lafs added the

labels 2012-02-16 18:04:45 +00:00

tahoe-lafs added this to the soon milestone 2012-02-16 18:04:45 +00:00

davidsarah commented

2012-02-16 18:15:24 +00:00

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Attachment 1678-incident-on-truncate.darcs.patch (73295 bytes) added

S3 backend: make truncated GET Bucket responses trigger an incident. Does not include tests. refs #1678 [depends on the patch for #1589 due to an import in s3_common.py needed by both.]This

**Attachment** 1678-incident-on-truncate.darcs.patch (73295 bytes) added S3 backend: make truncated GET Bucket responses trigger an incident. Does not include tests. refs #1678 [depends on the patch for #1589 due to an import in s3_common.py needed by both.]This

1678-incident-on-truncate.darcs.patch

72 KiB

davidsarah commented

2012-02-16 18:17:52 +00:00

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For some reason that patchfile doesn't include the change I recorded. Maybe a side-effect of using --ask-deps. Will fix.

davidsarah commented

2012-02-16 18:49:39 +00:00

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Attachment 1678-incident-on-truncate-v2.darcs.patch (49975 bytes) added

S3 backend: make truncated GET Bucket responses trigger an incident. Does not include tests. refs #1678 [depends on the patch for #1589 due to an import in s3_common.py needed by both.]This

**Attachment** 1678-incident-on-truncate-v2.darcs.patch (49975 bytes) added S3 backend: make truncated GET Bucket responses trigger an incident. Does not include tests. refs #1678 [depends on the patch for #1589 due to an import in s3_common.py needed by both.]This

1678-incident-on-truncate-v2.darcs.patch

49 KiB

davidsarah commented

2012-02-16 18:51:34 +00:00

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1678-incident-on-truncate-v2.darcs.patch (recorded without --ask-deps) seems to include the change. Odd.

[1678-incident-on-truncate-v2.darcs.patch](/tahoe-lafs/trac-2024-07-25/attachments/000078ac-504d-b508-82d2-c554f3ec0f23) (recorded without --ask-deps) seems to include the change. Odd.

zooko commented

2012-02-17 14:27:03 +00:00

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I review 1678-incident-on-truncate-v2.darcs.patch . I saw no error, but as David-Sarah mentioned, it needs a test.

I review [1678-incident-on-truncate-v2.darcs.patch](/tahoe-lafs/trac-2024-07-25/attachments/000078ac-504d-b508-82d2-c554f3ec0f23) . I saw no error, but as David-Sarah mentioned, it needs a test.

davidsarah commented

2012-02-20 18:03:49 +00:00

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Attachment 1678-incident-on-truncate-v3.darcs.patch (64604 bytes) added

S3 backend: make truncated GET Bucket responses trigger an incident. Includes tests and patches for #1589.

**Attachment** 1678-incident-on-truncate-v3.darcs.patch (64604 bytes) added S3 backend: make truncated GET Bucket responses trigger an incident. Includes tests and patches for #1589.

1678-incident-on-truncate-v3.darcs.patch

63 KiB

zooko commented

2012-02-20 18:41:43 +00:00

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Okay, I reviewed the added tests in 1678-incident-on-truncate-v3.darcs.patch and saw no problem!

Okay, I reviewed the added tests in [1678-incident-on-truncate-v3.darcs.patch](/tahoe-lafs/trac-2024-07-25/attachments/000078ac-504d-b508-82d2-c77eec8c06bd) and saw no problem!

davidsarah commented

2012-03-05 20:24:22 +00:00

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On secorp's LAE storage server, a 500 error (#1590) occurred after a sequence of truncated responses. With a bit of luck, the 500 might be a side effect of the truncated responses so that fixing the latter will also fix #1590.

tahoe-lafs added

critical

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major

labels 2012-03-05 20:24:22 +00:00

davidsarah commented

2012-03-09 00:15:56 +00:00

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Attachment s3-implement-prefix-queries.darcs.patch (142174 bytes) added

Implementation of prefix queries, for information only (doesn't fix the problem yet). Depends on txaws 0.2.1.post4, diff from 0.2.1 at https://leastauthority.com/static/patches/txAWS-0.2.1-to-post4.diff

**Attachment** s3-implement-prefix-queries.darcs.patch (142174 bytes) added Implementation of prefix queries, for information only (doesn't fix the problem yet). Depends on txaws 0.2.1.post4, diff from 0.2.1 at <https://leastauthority.com/static/patches/txAWS-0.2.1-to-post4.diff>

s3-implement-prefix-queries.darcs.patch

139 KiB

davidsarah commented

2012-03-09 00:27:08 +00:00

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I implemented prefix queries (so we no longer list all objects in the bucket and filter them, which is something that needed to be fixed anyway). That change seems to be working, and has given a measurable performance improvement of ~0.44 seconds per DHYB on secorp's server, but, it didn't stop the truncated responses as I expected. We no longer get lots of truncated responses with at or near 1000 objects, but we do still get occasional truncated responses with 0 or 1 objects. This makes no sense and is contrary to the S3 API documentation. Frustrating.

I implemented prefix queries (so we no longer list *all* objects in the bucket and filter them, which is something that needed to be fixed anyway). That change seems to be working, and has given a measurable performance improvement of ~0.44 seconds per DHYB on secorp's server, but, it didn't stop the truncated responses as I expected. We no longer get lots of truncated responses with at or near 1000 objects, but we do still get occasional truncated responses with 0 or 1 objects. This makes no sense and is contrary to the S3 API documentation. Frustrating.

davidsarah commented

2012-03-09 05:37:54 +00:00

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Actually the patch is basically correct. It appeared not to be because we were incorrectly reporting all queries as truncated. (I thought that BucketListing.is_truncated was a boolean rather than a string, and the string "false" is truthy. Down with implicit conversions!)

However, it turns out that truncated queries are not the cause of #1590 :-(

I'll post an updated patch for this ticket, fixing the incorrect detection of truncated queries, tomorrow.

Actually the patch is basically correct. It appeared not to be because we were incorrectly reporting all queries as truncated. (I thought that `BucketListing.is_truncated` was a boolean rather than a string, and the string `"false"` is truthy. Down with implicit conversions!) However, it turns out that truncated queries are *not* the cause of #1590 :-( I'll post an updated patch for this ticket, fixing the incorrect detection of truncated queries, tomorrow.

davidsarah commented

2012-05-17 00:24:03 +00:00

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Fixed mainly in [5634/ticket999-S3-backend].

tahoe-lafs added the

fixed

label 2012-05-17 00:24:03 +00:00

davidsarah closed this issue

2012-05-17 00:24:03 +00:00

tahoe-lafs modified the milestone from soon to 1.12.0

2014-11-27 04:08:46 +00:00