TODOs.md: Mark #task-fec292ff-b9de-4d6c-b156-a9adc4771f35 as done

1 files changed, 16 insertions, 1 deletions

diff --git a/TODOs.md b/TODOs.md
index 6f69278..9b263a8 100644
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+++ b/TODOs.md
@@ -50,7 +50,22 @@ The final period is marked as bold, too.
   [b0f64583bf02f84cadcfad9b610d9c02ec6c4ec2](https://git.euandreh.xyz/remembering/commit/?id=b0f64583bf02f84cadcfad9b610d9c02ec6c4ec2).
 - TODO in 2021-01-21
 
-## TODO Optimize for large lists {#task-fec292ff-b9de-4d6c-b156-a9adc4771f35}
+## DONE Optimize for large lists {#task-fec292ff-b9de-4d6c-b156-a9adc4771f35}
+- DONE in 2021-01-26
+
+  Instead of using `while read VAR < $FILE`, and looping through each record,
+  the `$MERGED` and `$FILTERED` files are built differently.
+
+  Building the `$MERGED` file exploits the fact that `sort -u -k2,2` picks the first
+  entry it sees, regardless of what is in column 1, or other columns. With that,
+  we feed the reversed (with `tac`) list to it, and `$MERGED` is built in a single
+  pass of sort.
+
+  Building the `$FILTERED` file is now done with a simple AWK script, that performs much
+  better that a `while read VAR < $FILE` loop.
+
+  Done in commit
+  [000b74b1140f2ac41cb5d00a9070db735abdc9c4](https://git.euandreh.xyz/remembering/commit/?id=000b74b1140f2ac41cb5d00a9070db735abdc9c4).
 - TODO in 2021-01-21
 
 ## DONE Add tests {#task-146fab37-e53b-489e-95d0-3fcdd4c3eaef}