Seattle record label Sub Pop has been a musical taste-maker for years as it has introduced the masses to such hip acts as Nirvana, Mudhoney, the Postal Service, Iron & Wine and the Shins.

Of those, Mudhoney and Iron & Wine will help celebrate the label’s 20th anniversary this weekend at Redmond’s Marymoor Park, with Flight of the Conchords, the Gutter Twins, the Vaselines and other acts. David Cross will headline a related comedy show tonight at Seattle’s Moore Theatre.

But the most talked about deal at SP20 is the reunion of Green River, the proto-grunge band that spawned Mudhoney, Pearl Jam and Mother Love Bone. It will play Sunday. So we caught up with Mudhoney’s Mark Arm to talk about getting the band back together.

When’s the last time you played with Green River?

The last time Green River really played was in ’87.

Have you gotten together since then?

(Mudhoney’s) Steve (Turner) and I played with (Pearl Jam’s) Jeff (Ament) and Stone (Gossard) at a Pearl Jam encore. We did, like, “Swallow My Pride” and I think maybe “Ain’t Nothin’ to Do” or something like that in ’93 – in Vegas. But, like, Alex (Vincent) wasn’t involved. Bruce (Fairweather) wasn’t involved. Chuck Treece, who played bass with Urge Overkill at the time … played drums. It wasn’t Green River so much as it was a disappointment to Pearl Jam fans.

So this is the first time in 21 years. What are the rehearsals like?

Well, we had two in April. And the first one was, of course, was a little shaky. But it wasn’t that bad. (Chuckles.) And by the second one things were startin’ to gel and everyone felt really positive about it. And then, of course, Pearl Jam went on tour. And then they came back, but we went on tour. And then we came back and they were already on tour again. … They get back today (the interview was last week), but we’re not actually gonna start practicin’ until the sixth.

Does that make you nervous?

A little, sure. But we’ve got, like … five full days dedicated to practicing. If we can’t get it together by then …

I imagine this brings back some memories playing these old songs you played back in the mid-’80s.

Yeah, I was kind of surprised, because I hadn’t thought of these songs for 20-plus years; I hadn’t sung ’em or anything. So I was kind of amazed how some of (the lyrics) came back pretty easily. And looking at it, I think everyone kind of (thought) “I’m not sure why we made this (song) as complicated as we did.”

What do you remember about starting the band?

Steve had joined my first band, Mr. Epp, for like the last six months of the band as a second guitar player. And that band fell apart, and Steve and I wanted to continue doing stuff. I was pretty broke at the time, and for some reason all my guitar equipment had fallen apart. … And so I was like, “I guess I’ll try singing in this next band and see if that works.”

We knew that we wanted to maybe try to get Jeff Ament in the band, because he was in a hard-core band called Deranged Diction. And he played with a distortion box in that band, which was something the bass player in Mr. Epp did. And he also jumped really high, and we thought, “Wow! That’s really cool.” (Laughs) You know, that was all it took.

In fact, we kind of went on this little campaign to recruit him to the point where Steve got a job at the same place where Jeff worked. Because we really didn’t know him. (Laughs)

So you were almost, like, stalking him.

Kind of, yes. (Laughs) We totally stalked Jeff. And then Alex went to high school with Steve and also Stone. But Stone wasn’t in the band right at the beginning.

Do you remember your first couple of gigs?

The very first show we played was at a storefront at 12th and Yesler in the (Seattle) Central District. Some friends of ours had this sort of a psychedelic Velvet Underground/Dream Syndicate kind of band called PMA, and they had a party at their place. They actually lived in this storefront.

Where did you envision taking this?

We envisioned taking it to the Gorilla Room, Natasha’s in Bremerton. Maybe Missoula if we get out there. (Laughs)

I ask because a lot of people point to Green River as a starting point for the whole weird grunge thing that happened after that.

I don’t know if that’s entirely the case. It’s kind of an easy thing to point at because both Pearl Jam and Mudhoney came out of that band. But, you know, the Melvins had been around for about a year or so by the time Green River started. And Malfunkshun had been around for a couple of years. They played with punk bands, but they were kind of almost this mock heavy-metal band.

So there were bands that had laid down a foundation.

Oh, sure. You could even look at what Black Flag was doing and point to that as the beginning of the whole thing. Black Flag started off as a totally fast hard-core band. And by “My War,” the second half of that album was totally three, long, slowed-down Black Sabbath/Flipper kind of songs.

That’s just kind of an easy shorthand thing for journalist or whoever to point to. But the truth is always more complicated and nuanced than most people are willing to (accept).

Ernest Jasmin: 253-274-7389

What: Sub Pop 20th anniversary festival

When: 8 p.m. today, noon Saturday and Sunday

Where: Comedy tonight at the Moore Theatre, 1932 Second Ave., Seattle; music Saturday and Sunday at Marymoor Park, 6046 W. Lake Sammamish Parkway N.E., Redmond

Tickets: $20 for tonight’s comedy show, $35 a day at Marymoor, $50 to $60 for both days

Information: Ticketmaster (253-627-8497 in Tacoma, 206-628-0888 in Seattle or www.ticketmaster.com)

On the Net: www.subpop.com