tools/show_segment_status/README.md

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This tool is used to get the progress of all current table transitions 
during the online `segment_2` function.

Currently, you can specify 3 dimensions (in the conf file) to view the 
results, you can specify one of them individually, or you can customize 
the combination (that is, specify multiple at the same time).

# Note
We use MySQLdb python lib to fetch meta from FE, so you must install it.

You can get MySQLdb lib from https://pypi.python.org/pypi/MySQL-python, 
then you can install it as follows:
```
$ tar zxvf MySQL-python-*.tar.gz
$ cd MySQL-python-*
$ python setup.py build
$ python setup.py install
``` 

# Steps
1. Fill in the conf according to your cluster configuration, and specify 
   the table or be you want to watch.
2. Execute `python show_segment_status.py`

# Example
1. If you want to watch the process of a table named `xxxx`, you can specify 
   `table_name = xxxx` in conf file

2. If you want to watch the process on be whose be_id is `xxxx`, you can specify 
   `be_id = xxxx` in conf file

# Output Example Format

The first number is about segment v2, the latter one is the total count.

```
==========SUMMARY()===========
rowset_count: 289845 / 289845
rowset_disk_size: 84627551189 / 84627551189
rowset_row_count: 1150899153 / 1150899153
===========================================================
==========SUMMARY(table=xxxx)===========
rowset_count: 289845 / 289845
rowset_disk_size: 84627551189 / 84627551189
rowset_row_count: 1150899153 / 1150899153
===========================================================
==========SUMMARY(be=10003 )===========
rowset_count: 79650 / 79650
rowset_disk_size: 24473921575 / 24473921575
rowset_row_count: 331449328 / 331449328
===========================================================
```