Problem: Background compaction IO error - too many files open causes puts to block forever

[trevorbernard]

If the background compaction errors, it silently causes the writes to hang forever. I would expect an error to be thrown.

    pub fn put_cf_opt<K, V>(
        &self,
        cf: &impl AsColumnFamilyRef,
        key: K,
        value: V,
        writeopts: &WriteOptions,
    ) -> Result<(), Error>
    where
        K: AsRef<[u8]>,
        V: AsRef<[u8]>,
    {
        let key = key.as_ref();
        let value = value.as_ref();

        unsafe {
            ffi_try!(ffi::rocksdb_put_cf(
                self.inner.inner(),
                writeopts.inner,
                cf.inner(),
                key.as_ptr() as *const c_char,
                key.len() as size_t,
                value.as_ptr() as *const c_char,
                value.len() as size_t,
            ));
            Ok(())
        }
    }

Setting the the no slowdown write option to true doesn't stop it from blocking

let mut writeopts = WriteOptions::default();
writeopts.set_no_slowdown(true);
self.db.put_cf_opt(&cf_handle, key, value, &writeopts)?;