html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/824#issuecomment-458809101,https://api.github.com/repos/pydata/xarray/issues/824,458809101,MDEyOklzc3VlQ29tbWVudDQ1ODgwOTEwMQ==,1217238,2019-01-30T04:37:36Z,2019-01-30T04:37:50Z,MEMBER,Yes it was,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-458808676,https://api.github.com/repos/pydata/xarray/issues/824,458808676,MDEyOklzc3VlQ29tbWVudDQ1ODgwODY3Ng==,2443309,2019-01-30T04:35:02Z,2019-01-30T04:35:02Z,MEMBER,"@shoyer - this was addressed in the backend refactor this summer, no?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-458108702,https://api.github.com/repos/pydata/xarray/issues/824,458108702,MDEyOklzc3VlQ29tbWVudDQ1ODEwODcwMg==,26384082,2019-01-28T12:13:51Z,2019-01-28T12:13:51Z,NONE,"In order to maintain a list of currently relevant issues, we mark issues as stale after a period of inactivity
If this issue remains relevant, please comment here; otherwise it will be marked as closed automatically
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-210640770,https://api.github.com/repos/pydata/xarray/issues/824,210640770,MDEyOklzc3VlQ29tbWVudDIxMDY0MDc3MA==,4295853,2016-04-15T20:47:08Z,2016-04-15T20:47:08Z,CONTRIBUTOR,"We could also just filter the other way too which is probably cleaner: 

``` python
if lock is None and type(file) is netCDF3:
   lock=False
```
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-210640015,https://api.github.com/repos/pydata/xarray/issues/824,210640015,MDEyOklzc3VlQ29tbWVudDIxMDY0MDAxNQ==,4295853,2016-04-15T20:45:15Z,2016-04-15T20:45:15Z,CONTRIBUTOR,"@shoyer, makes sense.  Are you thinking of something like the following pseudo code?

``` python
if lock is None:
    if type(file) is netCDF4/HDF5:
        lock=True
    else:
        lock=False
```
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-210633360,https://api.github.com/repos/pydata/xarray/issues/824,210633360,MDEyOklzc3VlQ29tbWVudDIxMDYzMzM2MA==,1217238,2016-04-15T20:33:29Z,2016-04-15T20:33:29Z,MEMBER,"The issues with multithreading without a lock come up only when using netCDF4/HDF5. With netCDF3, you don't need the lock when reading data.

I don't like changing to `lock=False` in all circumstances, because that will lead to segfaults and segfaults make for a bad new user experience! Instead, `lock=None` should do something smart.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289
https://github.com/pydata/xarray/issues/824#issuecomment-210629679,https://api.github.com/repos/pydata/xarray/issues/824,210629679,MDEyOklzc3VlQ29tbWVudDIxMDYyOTY3OQ==,4295853,2016-04-15T20:24:31Z,2016-04-15T20:24:31Z,CONTRIBUTOR,"@shoyer, is this related to https://github.com/pydata/xarray/pull/800?  If I recall correctly based on https://github.com/pydata/xarray/issues/793 there may be some issues with dask/multithreading without the lock.  Am I missing something here?

It may make sense to just to set `lock=False` by default in https://github.com/pydata/xarray/blob/master/xarray/backends/api.py#L247 and if issues are encountered `lock=True` can be set by the user.  Is this what you are thinking?  If so, I can submit the super simple PR if that is helpful.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,148757289