Error: No space left on device

Answer

This error has two possible causes: lack of space on one of the host file systems and a defect relating to unreleased memory semaphores.

Checking for Lack of Space on the File System

1. Log into the NPS server as the UNIX nz user.

2. Run the following command: df -k

3. Identify and clean up any file systems that are 100% full. The /tmp file system may be full because the Plan Optimizer uses it during the process of generating query execution plans.

Checking for Lack of Free Semaphores Defect

The second cause for the "No space left on device" error is a defect which is resolved in NPS 4.6 and later. In previous releases, a failed nzload job would not release its memory semaphores. If a system stayed up long enough, it could run out of free semaphores and generate this error.

1. Check for this condition by logging into the NPS server as the UNIX nz user.

2. Run the following command: ipcs -u -s

3. If the output shows the number of allocated semaphores is over 32,000, the condition exists. As the nz user, run the following commands:

nzstop

nzstart

Here is the output of ipcs -u -s before the nzstop:

------ Semaphore Status --------
used arrays = 32768
allocated semaphores = 33843

Here is the output of ipcs -u -s after the nzstart:

------ Semaphore Status --------
used arrays = 1287
allocated semaphores = 2362

As a side note, the actual error you see may contain a number as in the following example: "ERROR: 4533 : No space left on device". This number is not an error message identifier. In most cases, it is the amount of space that was requested when the problem occurred.