diff --git a/dbconn/Cargo.toml b/dbconn/Cargo.toml
index d7def8d..644a8e3 100644
--- a/dbconn/Cargo.toml
+++ b/dbconn/Cargo.toml
@@ -19,6 +19,7 @@ bincode = "1.3.3"
 #async-channel = "1"
 #dashmap = "3"
 tokio-postgres = { version = "0.7", features = ["runtime", "with-chrono-0_4", "with-serde_json-1"] }
+async-channel = "1.6"
 chrono = "0.4"
 regex = "1.5.4"
 err = { path = "../err" }
diff --git a/dbconn/src/lib.rs b/dbconn/src/lib.rs
index 4f2b26d..c58a55a 100644
--- a/dbconn/src/lib.rs
+++ b/dbconn/src/lib.rs
@@ -33,6 +33,20 @@ pub async fn create_connection(node_config: &NodeConfigCached) -> Result<Client,
     Ok(cl)
 }
 
+pub async fn create_connection_2(node_config: NodeConfigCached) -> Result<Client, Error> {
+    let d = &node_config.node_config.cluster.database;
+    let uri = format!("postgresql://{}:{}@{}:{}/{}", d.user, d.pass, d.host, 5432, d.name);
+    let (cl, conn) = tokio_postgres::connect(&uri, NoTls).await?;
+    // TODO monitor connection drop.
+    let _cjh = tokio::spawn(async move {
+        if let Err(e) = conn.await {
+            error!("connection error: {}", e);
+        }
+        Ok::<_, Error>(())
+    });
+    Ok(cl)
+}
+
 pub async fn channel_exists(channel: &Channel, node_config: &NodeConfigCached) -> Result<bool, Error> {
     let cl = create_connection(node_config).await?;
     let rows = cl
diff --git a/dbconn/src/scan.rs b/dbconn/src/scan.rs
index 12571d5..5259f21 100644
--- a/dbconn/src/scan.rs
+++ b/dbconn/src/scan.rs
@@ -1,15 +1,21 @@
+use async_channel::{bounded, Receiver, Sender};
 use chrono::{DateTime, Utc};
 use err::Error;
+use futures_core::Stream;
+use futures_util::FutureExt;
 use netpod::log::*;
 use netpod::NodeConfigCached;
 use serde::{Deserialize, Serialize};
 use std::future::Future;
 use std::io::ErrorKind;
+use std::marker::PhantomPinned;
 use std::os::unix::ffi::OsStringExt;
 use std::path::{Path, PathBuf};
 use std::pin::Pin;
+use std::ptr::NonNull;
+use std::sync::{Arc, RwLock};
+use std::task::{Context, Poll};
 use tokio_postgres::Client;
-use std::sync::{RwLock, Arc};
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct NodeDiskIdent {
@@ -67,34 +73,124 @@ where
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct UpdatedDbWithChannelNames {
+    msg: String,
     count: u32,
 }
 
-pub async fn update_db_with_channel_names(node_config: &NodeConfigCached) -> Result<UpdatedDbWithChannelNames, Error> {
-    let dbc = crate::create_connection(node_config).await?;
-    let node_ident = get_node_disk_ident(node_config, &dbc).await?;
-    let c1 = Arc::new(RwLock::new(0u32));
-    let rows = dbc
-        .query("select rowid from facilities where name = $1", &[&node_ident.facility])
-        .await?;
-    if rows.len() != 1 {
-        return Err(Error::with_msg(format!(
-            "can not find facility {}",
-            node_ident.facility
-        )));
+pub struct UpdatedDbWithChannelNamesStream {
+    errored: bool,
+    data_complete: bool,
+    node_config: Pin<Box<NodeConfigCached>>,
+    node_config_ptr: NonNull<NodeConfigCached>,
+    //_pin: PhantomPinned,
+    client_fut: Option<Pin<Box<dyn Future<Output = Result<Client, Error>> + Send>>>,
+    client: Option<Pin<Box<Client>>>,
+    client_ptr: *const Client,
+    ident_fut: Option<Pin<Box<dyn Future<Output = Result<NodeDiskIdent, Error>> + Send>>>,
+    ident: Option<NodeDiskIdent>,
+}
+
+unsafe impl Send for UpdatedDbWithChannelNamesStream {}
+
+impl UpdatedDbWithChannelNamesStream {
+    pub fn new(node_config: NodeConfigCached) -> Result<Self, Error> {
+        let node_config = Box::pin(node_config.clone());
+        let mut ret = Self {
+            errored: false,
+            data_complete: false,
+            node_config_ptr: NonNull::dangling(),
+            node_config,
+            //_pin: PhantomPinned,
+            client_fut: None,
+            client: None,
+            client_ptr: std::ptr::null(),
+            ident_fut: None,
+            ident: None,
+        };
+        ret.node_config_ptr = NonNull::from(&*ret.node_config);
+        ret.client_fut = Some(Box::pin(crate::create_connection(unsafe {
+            &*ret.node_config_ptr.as_ptr()
+        })));
+        Ok(ret)
     }
-    let facility: i64 = rows[0].try_get(0)?;
+}
+
+impl Stream for UpdatedDbWithChannelNamesStream {
+    type Item = Result<UpdatedDbWithChannelNames, Error>;
+
+    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>> {
+        use Poll::*;
+        'outer: loop {
+            break if self.errored {
+                Ready(None)
+            } else if self.data_complete {
+                Ready(None)
+            } else if let Some(fut) = &mut self.ident_fut {
+                match fut.poll_unpin(cx) {
+                    Ready(Ok(item)) => {
+                        self.ident = Some(item);
+                        self.ident_fut = None;
+                        let ret = UpdatedDbWithChannelNames {
+                            msg: format!("ALL DONE"),
+                            count: 42,
+                        };
+                        self.data_complete = true;
+                        Ready(Some(Ok(ret)))
+                    }
+                    Ready(Err(e)) => {
+                        self.errored = true;
+                        Ready(Some(Err(e)))
+                    }
+                    Pending => Pending,
+                }
+            } else if let Some(fut) = &mut self.client_fut {
+                match fut.poll_unpin(cx) {
+                    Ready(Ok(item)) => {
+                        self.client_fut = None;
+                        self.client = Some(Box::pin(item));
+                        self.client_ptr = self.client.as_ref().unwrap() as &Client as *const _;
+                        let p1 = unsafe { &*self.client_ptr };
+                        self.ident_fut = Some(Box::pin(get_node_disk_ident(
+                            unsafe { &*self.node_config_ptr.as_ptr() },
+                            &p1,
+                        )));
+                        let ret = UpdatedDbWithChannelNames {
+                            msg: format!("Client opened connection"),
+                            count: 42,
+                        };
+                        Ready(Some(Ok(ret)))
+                    }
+                    Ready(Err(e)) => {
+                        self.errored = true;
+                        Ready(Some(Err(e)))
+                    }
+                    Pending => Pending,
+                }
+            } else {
+                Ready(None)
+            };
+        }
+    }
+}
+
+pub async fn update_db_with_channel_names(
+    node_config: &NodeConfigCached,
+) -> Result<Receiver<Result<UpdatedDbWithChannelNames, Error>>, Error> {
+    let dbc = crate::create_connection(node_config).await?;
+    let node_disk_ident = get_node_disk_ident(node_config, &dbc).await?;
+    let c1 = Arc::new(RwLock::new(0u32));
     dbc.query("begin", &[]).await?;
     let dbc = Arc::new(dbc);
     find_channel_names_from_config(&node_config.node.data_base_path, |ch| {
         let ch = ch.to_owned();
         let dbc = dbc.clone();
         let c1 = c1.clone();
+        let fac = node_disk_ident.facility;
         async move {
             crate::delay_io_short().await;
             dbc.query(
                 "insert into channels (facility, name) values ($1, $2) on conflict do nothing",
-                &[&facility, &ch],
+                &[&fac, &ch],
             )
             .await?;
             let c2 = {
@@ -114,9 +210,10 @@ pub async fn update_db_with_channel_names(node_config: &NodeConfigCached) -> Res
     .await?;
     dbc.query("commit", &[]).await?;
     let ret = UpdatedDbWithChannelNames {
+        msg: format!("done"),
         count: *c1.read()?,
     };
-    Ok(ret)
+    Ok(bounded(16).1)
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -124,7 +221,9 @@ pub struct UpdatedDbWithAllChannelConfigs {
     count: u32,
 }
 
-pub async fn update_db_with_all_channel_configs(node_config: &NodeConfigCached) -> Result<UpdatedDbWithAllChannelConfigs, Error> {
+pub async fn update_db_with_all_channel_configs(
+    node_config: &NodeConfigCached,
+) -> Result<UpdatedDbWithAllChannelConfigs, Error> {
     let dbc = crate::create_connection(node_config).await?;
     let dbc = Arc::new(dbc);
     let node_disk_ident = &get_node_disk_ident(node_config, &dbc).await?;
@@ -178,9 +277,7 @@ pub async fn update_db_with_all_channel_configs(node_config: &NodeConfigCached)
         }
     }
     dbc.query("commit", &[]).await?;
-    let ret = UpdatedDbWithAllChannelConfigs {
-        count: c1,
-    };
+    let ret = UpdatedDbWithAllChannelConfigs { count: c1 };
     Ok(ret)
 }
 
diff --git a/httpret/src/lib.rs b/httpret/src/lib.rs
index 6f88c3c..f9448b9 100644
--- a/httpret/src/lib.rs
+++ b/httpret/src/lib.rs
@@ -171,6 +171,12 @@ async fn http_service_try(req: Request<Body>, node_config: &NodeConfigCached) ->
         } else {
             Ok(response(StatusCode::METHOD_NOT_ALLOWED).body(Body::empty())?)
         }
+    } else if path == "/api/4/update_search_cache" {
+        if req.method() == Method::GET {
+            Ok(update_search_cache(req, &node_config).await?)
+        } else {
+            Ok(response(StatusCode::METHOD_NOT_ALLOWED).body(Body::empty())?)
+        }
     } else if path.starts_with("/api/4/documentation/") {
         if req.method() == Method::GET {
             static_http!(path, "", "index.html", "text/html");
@@ -387,25 +393,35 @@ pub async fn clear_cache_all(req: Request<Body>, node_config: &NodeConfigCached)
     };
     let res = disk::cache::clear_cache_all(node_config, dry).await?;
     let ret = response(StatusCode::OK)
-    .header(http::header::CONTENT_TYPE, "application/json")
-    .body(Body::from(serde_json::to_string(&res)?))?;
+        .header(http::header::CONTENT_TYPE, "application/json")
+        .body(Body::from(serde_json::to_string(&res)?))?;
     Ok(ret)
 }
 
-pub async fn update_db_with_channel_names(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
+pub async fn update_db_with_channel_names(
+    req: Request<Body>,
+    node_config: &NodeConfigCached,
+) -> Result<Response<Body>, Error> {
     let (head, _body) = req.into_parts();
     let _dry = match head.uri.query() {
         Some(q) => q.contains("dry"),
         None => false,
     };
-    let res = dbconn::scan::update_db_with_channel_names(node_config).await?;
+    let res = dbconn::scan::UpdatedDbWithChannelNamesStream::new(node_config.clone())?;
+    //let res = dbconn::scan::update_db_with_channel_names(node_config).await?;
     let ret = response(StatusCode::OK)
-    .header(http::header::CONTENT_TYPE, "application/json")
-    .body(Body::from(serde_json::to_string(&res)?))?;
+        .header(http::header::CONTENT_TYPE, "application/json")
+        .body(Body::wrap_stream(res.map(|k| match serde_json::to_string(&k) {
+            Ok(item) => Ok(item),
+            Err(e) => Err(e),
+        })))?;
     Ok(ret)
 }
 
-pub async fn update_db_with_all_channel_configs(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
+pub async fn update_db_with_all_channel_configs(
+    req: Request<Body>,
+    node_config: &NodeConfigCached,
+) -> Result<Response<Body>, Error> {
     let (head, _body) = req.into_parts();
     let _dry = match head.uri.query() {
         Some(q) => q.contains("dry"),
@@ -417,3 +433,16 @@ pub async fn update_db_with_all_channel_configs(req: Request<Body>, node_config:
         .body(Body::from(serde_json::to_string(&res)?))?;
     Ok(ret)
 }
+
+pub async fn update_search_cache(req: Request<Body>, node_config: &NodeConfigCached) -> Result<Response<Body>, Error> {
+    let (head, _body) = req.into_parts();
+    let _dry = match head.uri.query() {
+        Some(q) => q.contains("dry"),
+        None => false,
+    };
+    let res = dbconn::scan::update_search_cache(node_config).await?;
+    let ret = response(StatusCode::OK)
+        .header(http::header::CONTENT_TYPE, "application/json")
+        .body(Body::from(serde_json::to_string(&res)?))?;
+    Ok(ret)
+}