diff --git a/src/os/unix/ngx_readv_chain.c b/src/os/unix/ngx_readv_chain.c
index a3577ce19..b1ae4b51d 100644
--- a/src/os/unix/ngx_readv_chain.c
+++ b/src/os/unix/ngx_readv_chain.c
@@ -96,7 +96,7 @@ ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *chain, off_t limit)
             iov->iov_len += n;
 
         } else {
-            if (vec.nelts >= IOV_MAX) {
+            if (vec.nelts == vec.nalloc) {
                 break;
             }