Long story or serial

I wonder about the better posting for long stories, say, over 5,000 words. Is it better to submit it whole, or break it into a series of short parts?
I have just written a story that became rather long, and I split it into two parts. Personally, I like the continuity of a single story, but many readers will not have the patience, unless it is really good.
I tend to have long build-ups, as I like to set the scene and establish context, but am aware this can be tedious to some.
What do people prefer, as a general rule?
It gets worse: my story has a part 3 brewing away.

This is an interesting question and the answer will be different for many people.
A longer story obviously requires more time to be able to read and appreciate it, so if you have time, it's fine, but if you have neither time nor patience, then you may not read it at all. The synopsis will help potential readers to decide if they think it worth spending the extended time necessary.
I personally would prefer a serial, so you can take little bites of a story and be eager to await the next part. However, I have found, to my dismay, that people often view the first parts of a story, but never follow through to the end, whether they like it or not, which is frustrating and in fact a real shame.
You can never win outright, so do what you feel is right and hope that people will read it. If they don't, it's their loss!

Elorac is right. Everyone is different, but certainly I'd say that when I sit down at the computer and see a story of 10,000 words I won't start it. Now this is strange because I'll happily read a paper book of much longer, but then of course there is the issue of the nature of the stories here and the difficulty of reading spanking stories when there are vanilla family members around. A short read can be more easily accommodated in the time available. A hard copy spanking story wouldn't get a look in.

Many authors are confused that some readers will view dissociated parts of a serial, sometimes even commenting effusively and yet not seeming to want to read more, either in or out of order.

Difficult really. I try to break the story up by spankings, so there is at least one per episode. Episodes tend to go between 1500 to 5000 words for me, at 6000 I usually try to make a rewrite, else I know that the readers will to a large extent have died from waiting for red skin to appear. Depending on the storyline there can of course be exceptions and I've read a handful of stories with a ten thousand word build-up that were excellent, but as others have pointed out, launching such you can expect way fewer views than if you can manage to break the story up in parts.

The number of views will drop from part to part no matter what you do. A lot of readers check the story out before it has been labelled and naturally the ones that realize that the plot is not at all to their liking or it's not their F/M, M/F, F/F, M/M or whatever kink scenario, will not read the subsequent parts. Once labelled more people tend to read several parts.

At the moment I tend to prefer 2 part or single stories. Series lose a lot of readers once they get 3 or longer, and long stories over 4K words seem to get the first part read and then the reader vanishes with no comments etc.

I do tend at times to skip around if a series has a number of no spanking parts in a row. I will also skip if there is say 1 f/my part in a series of m/f stories. I will go back sometime and fill in the lapses but it takes time.

CS

I've posted both - but I find that a story gets many more views if broken into parts. When a story hits somewhere around 5000 words I'll look at it and see if I can break it into chunks without losing the flow of the story, but if it's one long scene there's very little I can do.

I personally would go for the serial as a long story in its entirety can be off putting, if a reader wants a longer story then the serial provides that just in manageable chunks.

An aside also being, you might get more meaningful comments if it a serial (unsure if that is actually fact) as readers commenting on a part of story, so might be more precise in their comments rather than commenting on its entirety, though the option of just leaving comment at end of serial is still possible.

I concur with view that a spanking episode in each part holds my attention.

5000 words isn't that long. Personally I'd stick with one-shot story if it's under 8000 words. (But maybe I'm out to lunch; the only reason I have so many so-called 'serials' is because the site doesn't allow me to post 20,000-word stories...)
You're right that number of hits declines with each installment of a serial, but that's only an indicator of how many readers actually read it in the first place, not an indicator of flagging interest, necessarily. Even with one-shots, a healthy percentage of hits will be click-open-click-closed hits anyway, not true reads. (I'm certainly guilty of that. Sometimes it takes browsing 20 stories before I settle on actually reading one for real.)

So I would say your own assessment of the structure and flow of your story should decide whether or not you split it.

Well, in a few weeks I'll see what happens. Up until now I've been breaking larger stories into multiple parts. I hope that most readers agree with Burgundy that 5k words isn't that many because a lot of mine hit the 5k mark. Anyway, this particular story is ~8.5K and I vacillated between submitting it as a single story or multi-part before taking a chance with the former.

I second and third-guessed that decision but the deciding factor for me was that the website isn't here strictly for my benefit. There are only 30 "slots" available at every website update. So if I left the story whole then 29 other stories could get posted, but every subdivision would mean someone else's story (or maybe another of mine) would wind up waiting for the next update. So I figure that this tale might be long and not as well received, but at least you'll have additional options to read that week as a result of keeping it in one piece.

Interesting views, that pretty much cover the range.
I just checked and my story is only 6,500 words, so I needn't have split it. It was written as one story, then artificially divided; but there's action in both bits.
One technique to aid long build-up is to start with action as a prelude. I have done that at times.
I tend to write long stories in one go. There is obvious merit in short ones, and there are many excellent examples in the library. However, I like to set the scene and establish the characters, who are wasted in a short story. Many will not have the patience for the build-up, but like Burgundy, I like a solid context. If the story is good enough, people will keep reading - if relaxed enough with sufficient time.
I have a part 3 in mind, which will depend on the comments, I suppose. It might be a segment too far, but when I think of my own reading, often I have been unable to wait for a next instalment.