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Questions tagged [lmdb]

It is the mmap’d database for OpenLDAP aka Lightning MDB (LMDB).

It is the mmap’d database for OpenLDAP aka Lightning MDB (LMDB).

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caffe, training non-image data, constant loss and accuracy

I have created my own lmdb database consist of (non-image) 2D numpy lists values of data varies between 0 to MAX_INT. sample size is 1500*75, and the original is 15000*77 ( very slow to train). I have 2400 samples divided 5/6 for training and 1/6…
Heba Alawneh
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Caffe produces negative loss values (Multi label classification with lmdb)

I am trying to do multi label classification based on the lmdb database. I create two different databases. One for the images itself and one for the labels. My intention is to have 2 different labels for angles in horizontal and vertical direction.…
user4911648
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lmdb.open Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)

When I use python package LMDB to create a database, I got an error like this: Here is the code caused the erro: import lmbd db_labels = lmdb.open(lmdb_label_name, map_size=1e1) Actually, originally, the map_size is 1e12, some answers from here…
Junhao Wen
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No data is read when using lmdb cursor in Python

I have a lmdb database and I'm trying to read its contents. The irony is nothing gets printed on screen. This is the code snippet that I have written for reading from lmdb: import caffe import lmdb import numpy as np from caffe.proto import…
Hossein
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is data returned from lmdb invalidated after any change to the database?

the lmdb (Lightning Memory-Mapped Database) documentation mentions the following in regards to the validity of returned data: Values returned from the database are valid only until a subsequent update operation, or the end of the transaction. Do…
tantalum
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does lmdb support "recno" type, or workalike?

I'm playing w/ lmdb (coming from a BDB background) and wondering if lmdb supports "recno" style operation ? "recno" (record number) is a logical indexing method where the 20th record might be deleted, and a new record becomes the 20th record, or a…
bch
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Difference between LMDB and STX btrees

I would like to use in-memory btree. I am considering LMDB and STX. I appreciate help in understanding the difference between them. Among the others in context with concurrency (I'm not sure if STX supports it)
revit
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Shortest way to browse an LMDB in pandas under jupyter notebook

TLDR: How do I inspect \ browse an LMDB binary file? Complete py n00b here. I've just had an LMDB file dumped in my lap to analyze for data errors that are causing bugs in downstream software. I don't know the data schema and it's about 1 Gb in…
empty
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Image as a label for pixel wise classification using lmdb

I was having a problem for configuring caffe to do pixel wise segmentation. However, after research, I found that you can create another Imdb database for labels. I have done that, but I don't know how to link the data and label databases in the…
Ahmed Nadeem
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Converting mnist data to lmdb with python results very large database

I am currently playing the lenet model provided by caffe. the example (which is in path/to/caffe/examples/mnist/convert_mnist_data.cpp provides a c++ program to convert the mnist data to lmdb. I write a python program to do the same thing, but the…
alec.tu
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Values that can be stored in LMDB

LMDB is a key-value store. What types of keys and values can be stored here? Examples shows either int or char arrays.. Also I would like to know if it is possible to store related data in lmdb like we store all data related to a student in a table…
Jackzz
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how to embed LMDB database

I have heard of symas lightning memory mapped database, LMDB and went through the available documentations. How to use the database in Visual Studio? Also, is there something like Collections of MongoDB or table of RDBMS(I know LMDB is non SQL) in…
Jackzz
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Single Threaded LMDB

If you are using LMDB from only a single thread, and don't care about database persistence at all, is there any reason to open and close transactions? Will it cause a performance issue to do all operations within a single transaction? Is there a…
Jeremy Salwen
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lmdb no locks available error

I have a data.mdb and lock.mdb file in test/ directory. I was trying to use the python lmdb package to read/write data from the lmdb database. I tried import lmdb env = lmdb.open('test', map_size=(1024**3), readonly=True) but got the following…
AlexLi
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Segmentation error - get a row value in LMDB in C

How can I get the data from LMDB database? Here is the library - github.com/LMDB/lmdb/tree/mdb.master/libraries/liblmdb, and here is the lmdb file - github.com/LMDB/lmdb/blob/mdb.master/libraries/liblmdb/lmdb.h Here is my code, but it is not…
Sebastian Rockefeller
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