View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0007136 | GNUnet | DHT service | public | 2021-12-31 09:24 | 2022-02-26 23:10 |
| Reporter | schanzen | Assigned To | Christian Grothoff | ||
| Priority | normal | Severity | minor | Reproducibility | have not tried |
| Status | closed | Resolution | fixed | ||
| Product Version | Git master | ||||
| Target Version | 0.16.0 | Fixed in Version | 0.16.0 | ||
| Summary | 0007136: Distance metric update | ||||
| Description | We had offline discussions wrt the distance metric. Currently it is measured as uint64_t. I _think_ we said we want to change this to 512 bit (HashCode, same length as keys to compare) and use a more basic XOR metric. | ||||
| Tags | lsd0004 | ||||
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I also think the function definition is currently flawed and can be misunderstood: The "bucket" argument is not really referring to a bucket, but an offset to check. The get_distance() is preceded in the code by a matching_bits() call in order to find a "bucket": https://git.gnunet.org/gnunet.git/tree/src/dht/gnunet-service-dht_neighbours.c?id=9e0d7d411363999bca89f7e7b4e2896b8f6ec931#n1019 Now, IF matching_bits() is more efficient to call than the loop from index 0 in get_distance() we should do that, of course. But in get_distance()! Because a caller may assume the get_distance() "bucket" argument has actually something to do with buckets and will never know that instead of calling find_bucket() the matching_bits() function must be called to get an offset. It is just bad function signature design. I propose to simplify the get_distance() function to ONLY take two keys as argument. |
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I believe this has been resolved. |
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0.16.0 released |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2021-12-31 09:24 | schanzen | New Issue | |
| 2021-12-31 09:24 | schanzen | Status | new => assigned |
| 2021-12-31 09:24 | schanzen | Assigned To | => Christian Grothoff |
| 2021-12-31 09:24 | schanzen | Tag Attached: lsd0004 | |
| 2021-12-31 15:18 | schanzen | Note Added: 0018612 | |
| 2021-12-31 15:18 | schanzen | Note Edited: 0018612 | |
| 2021-12-31 15:19 | schanzen | Note Edited: 0018612 | |
| 2022-01-03 14:39 | Christian Grothoff | Note Added: 0018624 | |
| 2022-01-03 14:39 | Christian Grothoff | Status | assigned => resolved |
| 2022-01-03 14:39 | Christian Grothoff | Resolution | open => fixed |
| 2022-01-03 14:39 | Christian Grothoff | Fixed in Version | => 0.16.0 |
| 2022-02-26 23:10 | schanzen | Note Added: 0018742 | |
| 2022-02-26 23:10 | schanzen | Status | resolved => closed |
