diff --git a/configs/coins/bcash.json b/configs/coins/bcash.json
index d02d9739..40772e9b 100644
--- a/configs/coins/bcash.json
+++ b/configs/coins/bcash.json
@@ -52,7 +52,6 @@
             "address_format": "cashaddr",
             "mempool_workers": 8,
             "mempool_sub_workers": 2,
-            "mempool_resync_batch_size": 100,
             "block_addresses_to_keep": 300,
             "xpub_magic": 76067358,
             "slip44": 145,
diff --git a/configs/coins/bcash_testnet.json b/configs/coins/bcash_testnet.json
index 899c589d..ed4a690f 100644
--- a/configs/coins/bcash_testnet.json
+++ b/configs/coins/bcash_testnet.json
@@ -52,7 +52,6 @@
             "address_format": "cashaddr",
             "mempool_workers": 8,
             "mempool_sub_workers": 2,
-            "mempool_resync_batch_size": 100,
             "block_addresses_to_keep": 300,
             "xpub_magic": 70617039,
             "slip44": 1,
diff --git a/configs/coins/dogecoin.json b/configs/coins/dogecoin.json
index 5fa95b23..38f137e2 100644
--- a/configs/coins/dogecoin.json
+++ b/configs/coins/dogecoin.json
@@ -63,7 +63,6 @@
             "parse": true,
             "mempool_workers": 8,
             "mempool_sub_workers": 2,
-            "mempool_resync_batch_size": 100,
             "block_addresses_to_keep": 300,
             "xpub_magic": 49990397,
             "slip44": 3,
diff --git a/configs/coins/dogecoin_testnet.json b/configs/coins/dogecoin_testnet.json
index 02e43076..1d44c74b 100644
--- a/configs/coins/dogecoin_testnet.json
+++ b/configs/coins/dogecoin_testnet.json
@@ -65,7 +65,6 @@
       "parse": true,
       "mempool_workers": 8,
       "mempool_sub_workers": 2,
-      "mempool_resync_batch_size": 100,
       "block_addresses_to_keep": 300,
       "xpub_magic": 70617039,
       "slip44": 1,
diff --git a/configs/coins/litecoin.json b/configs/coins/litecoin.json
index 175038a9..4d1e43a9 100644
--- a/configs/coins/litecoin.json
+++ b/configs/coins/litecoin.json
@@ -59,7 +59,6 @@
             "parse": true,
             "mempool_workers": 8,
             "mempool_sub_workers": 2,
-            "mempool_resync_batch_size": 100,
             "block_addresses_to_keep": 300,
             "xpub_magic": 27108450,
             "xpub_magic_segwit_p2sh": 28471030,
diff --git a/configs/coins/litecoin_testnet.json b/configs/coins/litecoin_testnet.json
index 673158fc..8a158533 100644
--- a/configs/coins/litecoin_testnet.json
+++ b/configs/coins/litecoin_testnet.json
@@ -61,7 +61,6 @@
       "parse": true,
       "mempool_workers": 8,
       "mempool_sub_workers": 2,
-      "mempool_resync_batch_size": 100,
       "block_addresses_to_keep": 300,
       "xpub_magic": 70617039,
       "xpub_magic_segwit_p2sh": 71979618,
diff --git a/configs/coins/zcash.json b/configs/coins/zcash.json
index 1d2e58b3..9cab054f 100644
--- a/configs/coins/zcash.json
+++ b/configs/coins/zcash.json
@@ -50,7 +50,6 @@
             "parse": true,
             "mempool_workers": 4,
             "mempool_sub_workers": 8,
-            "mempool_resync_batch_size": 100,
             "block_addresses_to_keep": 300,
             "xpub_magic": 76067358,
             "slip44": 133,
diff --git a/configs/coins/zcash_testnet.json b/configs/coins/zcash_testnet.json
index c96933cd..60ede9ef 100644
--- a/configs/coins/zcash_testnet.json
+++ b/configs/coins/zcash_testnet.json
@@ -56,7 +56,6 @@
       "parse": true,
       "mempool_workers": 4,
       "mempool_sub_workers": 8,
-      "mempool_resync_batch_size": 100,
       "block_addresses_to_keep": 300,
       "xpub_magic": 70617039,
       "slip44": 1,
diff --git a/tests/rpc/rpc.go b/tests/rpc/rpc.go
index 0e5c9f3f..71cb4dd2 100644
--- a/tests/rpc/rpc.go
+++ b/tests/rpc/rpc.go
@@ -271,15 +271,20 @@ func testMempoolSync(t *testing.T, h *TestHandler) {
 			continue
 		}
 
+		beforeIntersect := len(txs)
 		txs = intersect(txs, getMempool(t, h))
 		if len(txs) == 0 {
 			// no transactions to test
 			continue
 		}
-		const maxMempoolSyncTxs = 200
-		if len(txs) > maxMempoolSyncTxs {
-			txs = txs[:maxMempoolSyncTxs]
+		if beforeIntersect >= 20 {
+			ratio := float64(len(txs)) / float64(beforeIntersect)
+			if ratio < 0.2 {
+				t.Fatalf("mempool intersect too small: after=%d before=%d ratio=%.2f", len(txs), beforeIntersect, ratio)
+			}
 		}
+		const mempoolSyncStride = 5
+		txs = sampleEveryNth(txs, mempoolSyncStride)
 
 		txid2addrs := getTxid2addrs(t, h, txs)
 		if len(txid2addrs) == 0 {
@@ -578,6 +583,17 @@ func intersect(a, b []string) []string {
 	return res
 }
 
+func sampleEveryNth(txs []string, stride int) []string {
+	if stride <= 1 || len(txs) <= stride {
+		return txs
+	}
+	sampled := make([]string, 0, (len(txs)+stride-1)/stride)
+	for idx := 0; idx < len(txs); idx += stride {
+		sampled = append(sampled, txs[idx])
+	}
+	return sampled
+}
+
 func containsTx(o []bchain.Outpoint, tx string) bool {
 	for i := range o {
 		if o[i].Txid == tx {