LMDB error on Ubuntu

Question

I was going through the MNIST tutorial in caffe2 and I ran into the following error:

RuntimeError: [enforce fail at db.h:190] db_. Cannot open db: /home/Aakash/caffe2_notebooks/tutorial_data/mnist/mnist-train-nchw-lmdb of type lmdb Error from operator: 
output: "dbreader_/home/Aakash/caffe2_notebooks/tutorial_data/mnist/mnist-train-nchw-lmdb" name: "" type: "CreateDB" arg { name: "db_type" s: "lmdb" } arg { name: "db" s: "/home/Aakash/caffe2_notebooks/tutorial_data/mnist/mnist-train-nchw-lmdb" }

Why is this happening?

do you have the lmdb file on your disk? do you have reading permissions for the database? — Shai, Jul 27 '17 at 11:23
is it possible someone else is accessing the lmdb at the same time? is it possible you have other process suspended that was accessing the lmdb? — Shai, Jul 27 '17 at 11:46
No. I am following this tutorial. https://github.com/caffe2/caffe2/blob/master/caffe2/python/tutorials/MNIST.ipynb — user3125971, Jul 27 '17 at 11:51
Did you ever find a solution to this problem? I am experiencing same issue now. — Mink, Dec 07 '17 at 17:52

score 0 · Answer 1 · answered Jun 23 '18 at 20:26

Was struggling with this the whole day and finally found the solution.

I am using Python's Anaconda distribution and was facing same issue.

Make following changes inside < CAFFE_ROOT >/scripts/build_anaconda.sh:

-caffe2_cmake_args+=("-DUSE_LMDB=OFF")
+caffe2_cmake_args+=("-DUSE_LMDB=ON")

And then run ./scripts/build_anaconda.sh --install-locally to build the caffe2 source for anaconda.

LMDB error on Ubuntu

1 Answers1