Error: Assertion `closest_vid>=0' failed. How to solve?

[Guan Wang]

Dear all,

When I run my graph with around 800 million nodes, graphchi stops and gives the following error:

connectedcomponents: ./src/shards/slidingshard.hpp:278: void graphchi::sliding_shard<VT, ET, svertex_t, ETspecial>::move_close_to(graphchi::vid_t) [with VT = int; ET = char; svertex_t = graphchi::graphchi_vertex<int, char>; ETspecial = char; graphchi::vid_t = unsigned int]: Assertion `closest_vid>=0' failed.

connectedcomponents: ./src/shards/slidingshard.hpp:278: void graphchi::sliding_shard<VT, ET, svertex_t, ETspecial>::move_close_to(graphchi::vid_t) [with VT = int; ET = char; svertex_t = graphchi::graphchi_vertex<int, char>; ETspecial = char; graphchi::vid_t = unsigned int]: Assertion `closest_vid>=0' failed.

Aborted (core dumped)

I Googled and it seems this error corresponds to number of nodes exceeding MAX INT32. However I don't think this is my case. Can anyone help me on how to solve this problem? Thank you!

Best,

Guan

[Aapo Kyrola]

Hi,

can you paste your full log output? It is likely problem that the disk has
run out of space or the number of shards is too low given the amount of
memory you have available.

Aapo

> --
> You received this message because you are subscribed to the Google Groups
> "graphchi-discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to graphchi-discu...@googlegroups.com. To post to this
> group, send email to graphchi...@googlegroups.com. To view this
> discussion on the web visit
> https://groups.google.com/d/msgid/graphchi-discuss/bec56800-6383-4ae6-969
> a-9abb036eb505%40googlegroups.com. For more options, visit
> https://groups.google.com/d/optout.
>
>

[Guan Wang]

Hi, please find the log in the attachment. Thank you!

Best,

Guan

[Aapo Kyrola]

Hi Guan,

it seems you have vertex IDs that are larger than the 32-bit signed
integer (about 2.1 billion):
(Degree proc.) Sub-window: [2147677601 - 2152677601]

Unfortunately GraphChi does support only 32 bit vertex IDs. You can try to
compile a version of GraphChi which uses 64 bit vertex IDs by changing the
vertex id type to uint64_t:
https://github.com/GraphChi/graphchi-cpp/blob/master/src/graphchi_types.hpp#L26

You probably need to do several other changes to the code as well,
unfortunately, so I don't recommend it. Can you cast your IDs to be less
than 2 billion?

Aapo

>>> email to graphchi-discu...@googlegroups.com <javascript:>. To post to
>>>
>> this
>>> group, send email to graphchi...@googlegroups.com <javascript:>. To

>> view this
>>> discussion on the web visit
>>>
>> https://groups.google.com/d/msgid/graphchi-discuss/bec56800-6383-4ae6-9
>> 69
>>
>>> a-9abb036eb505%40googlegroups.com. For more options, visit
>>> https://groups.google.com/d/optout.
>>>
>>>
>>>
>>
>>
>>
>
> --
> You received this message because you are subscribed to the Google Groups
> "graphchi-discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to graphchi-discu...@googlegroups.com. To post to this
> group, send email to graphchi...@googlegroups.com. To view this
> discussion on the web visit

> https://groups.google.com/d/msgid/graphchi-discuss/c61d092d-8a1b-445e-9bc
> 1-e744e4292c70%40googlegroups.com.

[Guan Wang]

Hi, Aapo. This is strange because my largest node ID is only slightly larger than 800 million. I was trying the connected components example app, is the algorithm generating some temporary nodes during the process?

Anyway I will recompile graphchi trying to replace all the int_32 type into int_64 and run again. Thank you!

Best,
Guan

[Aapo Kyrola]

There is probably something wrong in the dataset. I suggest you modify the
parser of the data in conversions.hpp to fail if there is an id larger
than 800 million (or smaller than 0).

Aapo

> --
> You received this message because you are subscribed to the Google Groups
> "graphchi-discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to graphchi-discu...@googlegroups.com. To post to this
> group, send email to graphchi...@googlegroups.com. To view this
> discussion on the web visit

> https://groups.google.com/d/msgid/graphchi-discuss/9775be6f-f6e3-42bb-995
> f-45cba567441b%40googlegroups.com. For more options, visit
> https://groups.google.com/d/optout.
>
>