failure in block hash tree

[midnightmagic]

Running tahoe on the machine in which python2.5 setup.py test fails as reported in trac ticket#737, generates the attached incident report.

Brief summary from flog debugger viewer:

<ValidatedReadBucketProxy? #1>(2-<ReadBucketProxy? 150097484 to peer [mgnbpxki] SI jow42sylefxjxsns3alv5ptghe>-m2st7xk76cvd): hash failure in block=0, shnum=2 on <ReadBucketProxy? 150097484 to peer [mgnbpxki] SI jow42sylefxjxsns3alv5ptghe>

[...]

<BlockDownloader? #2>(<ValidatedReadBucketProxy? #3>-2): failure to get block

[... etc ...]

failure in block hash tree

.. and so on.

Actual cli error message is:

tahoe get URI:CHK:lapry55oui4psmeiyxhvitfmpi:75mb37to6iauypych6bkqfkxxxfk6nhekhomzipkqzwt46v64hdq:3:5:99758080 meh Error, got 410 Gone NotEnoughSharesError?: no shares could be found. Zero shares usually indicates a corrupt URI, or that no servers were connected, but it might also indicate severe corruption. You should perform a filecheck on this object to learn more.

Finally, dump-share on the 33MB file:

share filename: /v/tahoe/.tahoe/storage/shares/jo/jow42sylefxjxsns3alv5ptghe/2

version: 1

file_size: 99758080

num_segments: 762 segment_size: 131073

needed_shares: 3

total_shares: 5

codec_name: crs

codec_params: 131073-3-5

tail_codec_params: 11529-3-5

crypttext_hash: zodzh33f7mnowsxine5mzejiahlxsilgggpxmop5bfrh4zzzdpha

crypttext_root_hash: nuqsysg5zqkz5nsvpi32n5h6h5ilbepsbvmssji2xv773kqw53tq

share_root_hash: m2st7xk76cvdutgf5lzmkdzbf72h75cxpkytwjegi5jgntir3u5q

UEB_hash: 75mb37to6iauypych6bkqfkxxxfk6nhekhomzipkqzwt46v64hdq

verify-cap: URI:CHK-Verifier:jow42sylefxjxsns3alv5ptghe:75mb37to6iauypych6bkqfkxxxfk6nhekhomzipkqzwt46v64hdq:3:5:99758080

Size of data within the share:

data: 33252694

uri-extension: 325

validation: 196648

Lease #0: owner=0, expire in 2607324s (30 days)

Machine details:

NetBSD quickie 4.99.7 NetBSD 4.99.7 (quickie) #0: Tue Jan 2 14:47:23 PST 2007 root@quickie:/v/src/sys/arch/i386/compile/quickie i386

AMD Athlon(tm) XP 2500+ (single-core, 32-bit) 2.5GB RAM

Python 2.5.2

This is a transitional pthread machine, partway between the M:N -> 1:1 threading model transition. The M:N threads *should* be functional and for all system and most application purposes they are. (KDE, etc.) However, on occasion some software makes assumptions or is built without threading support because configure detected anomalous behaviour.

NOTE: The share file IS AVAILABLE UPON REQUEST. I will save it for posterity.

[midnightmagic]

Incident report. View with: flogtool web-viewer -p 8081 incident-2009-06-16-211442-qvfj7eq.flog.bz2